Perceived performance - Learn web development
relevant measurements include first meaningful paint (fmp), largest contentful paint (lcp), time to interactive (tti), render start, dom interactive, and speed index.
... speed index is also used to approximate perceived performance: it measures the average time for pixels on the visible screen to be painted.
...however, you don't have to know the ins and outs of how everything, including how the human mind works, to improve the perception of speed.
...now that we know what we should be speeding up, let's take a look at some metrics and learn how we can measure these events.

The "why" of web performance - Learn web development
with performance as with accessibility, you consider what device a site visitor is using to access the site and the device connection speed.
... the speed at which a site loads is one factor.
...site speed directly affects bounce rates, conversion, revenue, user satisfaction, and search engine ranking.
...multiple factors, including network speed and device capabilities affect performance.

AudioBufferSourceNode.playbackRate - Web APIs
the playbackrate property of the audiobuffersourcenode interface is a k-rate audioparam that defines the speed at which the audio asset will be played.
... a value of 1.0 indicates it should play at the same speed as its sampling rate, values less than 1.0 cause the sound to play more slowly, while values greater than 1.0 result in audio playing faster than normal.
...let's see what a few values of playbackrate do: a playbackrate of 1.0 plays the audio at full speed, or 44,100 hz.
... a playbackrate of 0.5 plays the audio at half speed, or 22,050 hz.

Basic animations - Web APIs
it takes a lot of time to redraw complex frames and the performance depends highly on the speed of the computer it's running on.
... var img = new image(); // user variables - customize these to change the image being scrolled, its // direction, and the speed.
... img.src = 'https://mdn.mozillademos.org/files/4553/capitan_meadows,_yosemite_national_park.jpg'; var canvasxsize = 800; var canvasysize = 200; var speed = 30; // lower is faster var scale = 1.05; var y = -4.5; // vertical offset // main program var dx = 0.75; var imgw; var imgh; var x = 0; var clearx; var cleary; var ctx; img.onload = function() { imgw = img.width * scale; imgh = img.height * scale; if (imgw > canvasxsize) { // image larger than canvas x = canvasxsize - imgw; } if (imgw > canvasxsize) { // image width larger than canvas clearx = imgw; } else { clearx = canvasxsize; } if (imgh > canvasysize) { // image height larger than canvas cleary = imgh; } else { cleary = canvasysize; ...
... } // get canvas context ctx = document.getelementbyid('canvas').getcontext('2d'); // set refresh rate return setinterval(draw, speed); } function draw() { ctx.clearrect(0, 0, clearx, cleary); // clear the canvas // if image is <= canvas size if (imgw <= canvasxsize) { // reset, start from beginning if (x > canvasxsize) { x = -imgw + x; } // draw additional image1 if (x > 0) { ctx.drawimage(img, -imgw + x, y, imgw, imgh); } // draw additional image2 if (x - imgw > 0) { ctx.drawimage(img, -imgw * 2 + x, y, imgw, imgh); } } // image is > canvas size else { // reset, start from beginning if (x > (canvasxsize)) { x = c...

transition-timing-function - CSS: Cascading Style Sheets
this, in essence, lets you establish an acceleration curve so that the speed of the transition can vary over its duration.
... linear equal to cubic-bezier(0.0, 0.0, 1.0, 1.0), transitions at an even speed.
... ease-in equal to cubic-bezier(0.42, 0, 1.0, 1.0), starts off slowly, with the transition speed increasing until complete.
...• ease-in-out equal to cubic-bezier(0.42, 0, 0.58, 1.0), starts transitioning slowly, speeds up, and then slows down again.

image-rendering - SVG: Scalable Vector Graphics
the image-rendering attribute provides a hint to the browser about how to make speed vs.
... as a presentation attribute, it can be applied to any element but it has effect only on the following element: <image> usage notes value auto | optimizespeed | optimizequality default value auto animatable yes auto indicates that the user agent shall make appropriate tradeoffs to balance speed and quality, but quality shall be given more importance than speed.
... optimizespeed indicates that the user agent shall emphasize rendering speed over quality.
... optimizequality indicates that the user agent shall emphasize quality over rendering speed.

shape-rendering - SVG: Scalable Vector Graphics
following seven elements: <circle>, <ellipse>, <line>, <path>, <polygon>, <polyline>, and <rect> html, body, svg { height: 100%; } <svg viewbox="0 0 420 200" xmlns="http://www.w3.org/2000/svg"> <circle cx="100" cy="100" r="100" shape-rendering="geometricprecision"/> <circle cx="320" cy="100" r="100" shape-rendering="crispedges"/> </svg> usage notes value auto | optimizespeed | crispedges | geometricprecision default value auto animatable yes auto this value indicates that the user agent shall make appropriate tradeoffs to balance speed, crisp edges and geometric precision, but with geometric precision given more importance than speed and crisp edges.
... optimizespeed this value indicates that the user agent shall emphasize rendering speed over geometric precision and crisp edges.
... crispedges this value indicates that the user agent shall attempt to emphasize the contrast between clean edges of artwork over rendering speed and geometric precision.
... geometricprecision indicates that the user agent shall emphasize geometric precision over speed and crisp edges.

text-rendering - SVG: Scalable Vector Graphics
be applied to any element but it has effect only on the following element: <text> html, body, svg { height: 100%; } <svg viewbox="0 0 140 40" xmlns="http://www.w3.org/2000/svg"> <text y="15" text-rendering="geometricprecision">geometric precision</text> <text y="35" text-rendering="optimizelegibility">optimized legibility</text> </svg> usage notes value auto | optimizespeed | optimizelegibility | geometricprecision default value auto animatable yes auto this value indicates that the user agent shall make appropriate tradeoffs to balance speed, legibility and geometric precision, but with legibility given more importance than speed and geometric precision.
... optimizespeed this value indicates that the user agent shall emphasize rendering speed over legibility and geometric precision.
... optimizelegibility this value indicates that the user agent shall emphasize legibility over rendering speed and geometric precision.
... geometricprecision this value indicates that the user agent shall emphasize geometric precision over legibility and rendering speed.

From object to iframe — other embedding technologies - Learn web development
these were considered the height of coolness in the mid to late 90s, and there was evidence that having a webpage split up into smaller chunks like this was better for download speeds — especially noticeable with network connections being so slow back then.
... they did however have many problems, which far outweighed any positives as network speeds got faster, so you don't see them being used anymore.
... note: in order to improve speed, it's a good idea to set the iframe's src attribute with javascript after the main content is done with loading.

Measuring performance - Learn web development
these can generally be classified into two categories: tools that indicate or measure performance, such as pagespeed insights or the firefox network monitor and performance monitor.
... general performance reporting tools tools like pagespeed insights can measure a website’s performance.
... try running your favorite website now, on both webpagetest.org and pagespeed insights, and see what the scores are.

Property cache
spidermonkey's property cache is an internal data structure used to speed up property accesses in the interpreter and to communicate between the interpreter and jit.
...when executing certain property-accessing bytecode instructions, the interpreter populates the cache to speed future execution of the same instruction.
...the jit ensures this by using the property cache to forward its work to the interpreter.) for speed, the cache is a fixed-size hash table with no chaining.

HTMLMarqueeElement - Web APIs
note that any value smaller than 60 is ignored and the value 60 is used instead, unless truespeed is true.
... htmlmarqueeelement.truespeed by default, scrolldelay values lower than 60 are ignored.
... if truespeed is true, then those values are not ignored.

HTMLMediaElement.playbackRate - Web APIs
the normal playback rate is multiplied by this value to obtain the current rate, so a value of 1.0 indicates normal speed.
... the pitch of the audio is corrected by default and is the same for every speed.
...1.0 is "normal speed," values lower than 1.0 make the media play slower than normal, higher values make it play faster.

MediaPositionState - Web APIs
playbackrate a floating-point value indicating the rate at which the media is being played, as a ratio relative to its normal playback speed.
... thus, a value of 1 is playing at normal speed, 2 is playing at double speed, and so forth.
... negative values indicate that the media is playing in reverse; -1 indicates playback at the normal speed but backward, -2 is double speed in reverse, and so on.

animation-timing-function - CSS: Cascading Style Sheets
linear equal to cubic-bezier(0.0, 0.0, 1.0, 1.0), animates at an even speed.
... ease-in equal to cubic-bezier(0.42, 0, 1.0, 1.0), starts off slowly, with the speed of the transition of the animating properting increasing until complete.
...• ease-in-out equal to cubic-bezier(0.42, 0, 0.58, 1.0), with the animating properties slowly transitioning, speeding up, and then slowing down again.

<easing-function> - CSS: Cascading Style Sheets
this lets you vary the animation's speed over the course of its duration.
... ease-in the animation starts slowly, and then progressively speeds up until the end, at which point it stops abruptly.
... ease-in-out the animation starts slowly, speeds up, and then slows down towards the end.

<marquee>: The Marquee element (Obsolete) - HTML: Hypertext Markup Language
note that any value smaller than 60 is ignored and the value 60 is used instead, unless truespeed is specified.
... truespeed by default, scrolldelay values lower than 60 are ignored.
... if truespeed is present, those values are not ignored.

Populating the page: how browsers work - Web Performance
after this initial request, the ip will likely be cached for a time, which speeds up subsequent requests by retrieving the ip address from the cache instead of contacting a name server again.
...this is part of tcp slow start, an algorithm which balances the speed of a network connection.
...tcp slow start gradually builds up transmission speeds appropriate for the network's capabilities to avoid congestion.

Understanding latency - Web Performance
we can determine the amount of latency by measuring the speed with which the data moves from one network location to another.
...different browser developer tools have different preset options, the characteristics emulated include download speed, upload speed, and minimum latency, or the minimum amount of type it takes to send a packet of data.
... the approximate values of some presets include: selection download speed upload speed minimum latency (ms) gprs 50 kbps 20 kbps 500 regular 2g 250 kbps 50 kbps 300 good 2g 450 kbps 150 kbps 150 regular 3g 750 kbps 250 kbps 100 good 3g 1.5 mbps 750 kbps 40 regular 4g/lte 4 mbps 3 mbps 20 dsl 2 mbps 1 mbps 5 wi-fi 30 mbps 15 mbps 2 network timings also, on the network tab, you can see how long each request took to complete.

Appendix D: Loading Scripts - Archive of obsolete content
speed: script tags may or may not be loaded from pre-compiled bytecode in the fastload cache (gecko 1.x) or startup cache (gecko 2), which means they don't necessarily need to read as source and compiled with each restart.
... speed: even if these scripts are loaded from a cache, only read and compile time are reduced.

Kill the XUL.mfl file for good - Archive of obsolete content
this is meant to speed up the operation of mozilla, however in a fileserver based environment, this can be problematic: at several megabytes a pop, these files will take up a considerable amount of space, because each user has his own...
... with quicklauncer (see above), mozilla's speed is actually quite adequate, even without xul.mfl for these reasons, it is desirable to disable the xul.mfl functionality.

Sunbird Theme Tutorial - Archive of obsolete content
it is usual to turn off compression so that your theme's speed is maximized.
...it is usual to turn off compression so that your theme's speed is maximized.

The Business Benefits of Web Standards - Archive of obsolete content
introduction and context doing more with less seems to be the mission impossible for web designers: addressing more customers, a broader audience, more diversity in terms of browsers, more accessibility, users asking for more speed, while spending less to maintain or redesign a web site.
...according to various reports, case studies, and andy king, author of speed up your web site: web site optimization, css has made it possible to transform table-based layouts into css-based layouts.

2D maze game with device orientation - Game development
the phaser framework provides you with a set of tools that will speed up development and help handle generic tasks needed to complete the game, so you can focus on the game idea itself.
...without the framework, to add the canvas element to the page, you would have to write something like this inside the <body> tag: <canvas id='game' width='320' height='480'></canvas> the important thing to remember is that the framework is setting up helpful methods to speed up a lot of things like image manipulation or assets management, which would be a lot harder to do manually.

TCP slow start - MDN Web Docs Glossary: Definitions of Web-related terms
tcp slow start helps buildup transmission speeds to the network's capabilities.
...tcp slow start is an algorithm used to detect the available bandwidth for packet transmission, and balances the speed of a network connection.

Web performance resources - Learn web development
pagespeed insights can analyze your page and give some general hints to improve performance.
... test your page's speed using webpagetest.org, where you can use different real device types and locations.

Introduction to the server side - Learn web development
web frameworks are collections of functions, objects, rules and other code constructs designed to solve common problems, speed up development, and simplify the different types of tasks faced in a particular domain.
... note: client-side frameworks are often used to help speed up development of client-side code, but you can also choose to write all the code by hand; in fact, writing your code by hand can be quicker and more efficient if you only need a small, simple web site ui.

Server-side web frameworks - Learn web development
performance of the framework/programming language: usually "speed" is not the biggest factor in selection because even relatively slow runtimes like python are more than "good enough" for mid-sized sites running on moderate hardware.
... the perceived speed benefits of another language, e.g.

Getting started with Ember - Learn web development
increasing cohesion among many team's technology stacks community-backed "best practices" allow for faster long-term development speed.
... ember has clear conventions that are useful for enforcing consistency and helping team members get up to speed quickly.

Introduction to automated testing - Learn web development
using a task runner to automate testing tools as we said above, you can drastically speed up common tasks such as linting and minifying code by using a task runner to run everything you need to run automatically at a certain point in your build process.
... using commercial testing services to speed up browser testing now let's look at commercial third-party browser testing services and what they can do for us.

Cross browser testing - Learn web development
what users, browsers, and devices do you most need to worry about?), how to go about doing testing, the main issues that you'll face with different types of code and how to mitigate them, what tools are most useful in helping you test and fix problems, and how to use automation to speed up testing.
...this article details how to write your own simple feature detection, how to use a library to speed up implementation, and native features for feature detection such as @supports.

Configuring Build Options
disabling these tests can speed build time and reduce disk space considerably.
... ac_add_options --with-ccache=/path/to/.mozbuild/sccache/sccache this enables sccache to speed up builds.

Index
13 jit optimization outcomes beginner, firefox, intro, needscontent, spidermonkey spidermonkey's optimizing jit, ionmonkey, uses different optimization strategies to speed up various operations.
... 534 property cache spidermonkey spidermonkey's property cache is an internal data structure used to speed up property accesses in the interpreter and to communicate between the interpreter and jit.

Responsive Design Mode - Firefox Developer Tools
the characteristics emulated are: download speed upload speed minimum latency the table below lists the numbers associated with each network type, but please do not rely on this feature for exact performance measurements; it's intended to give an approximate idea of the user experience in different conditions.
... selection download speed upload speed minimum latency (ms) gprs 50 kb/s 20 kb/s 500 regular 2g 250 kb/s 50 kb/s 300 good 2g 450 kb/s 150 kb/s 150 regular 3g 750 kb/s 250 kb/s 100 good 3g 1.5 mb/s 750 kb/s 40 regular 4g/lte 4 mb/s 3 mb/s 20 dsl 2 mb/s 1 mb/s 5 wi-fi 30 mb/s 15 mb/s 2 to select a network, click the list box that's initially labeled "no throttling": ...

AudioBufferSourceNode.AudioBufferSourceNode() - Web APIs
detune: a value in cents to modulate the speed of audio stream rendering.
... playbackrate: the speed at which to render the audio stream.

AudioBufferSourceNode - Web APIs
this value is compounded with playbackrate to determine the speed at which the sound is played.
... audiobuffersourcenode.playbackrate an a-rate audioparam that defines the speed factor at which the audio asset will be played, where a value of 1.0 is the sound's natural sampling rate.

AudioListener - Web APIs
audiolistener.speedofsound is a double value representing the speed of sound, in meters per second.
... in a previous version of the specification, the dopplerfactor and speedofsound properties and the setposition() method could be used to control the doppler effect applied to audiobuffersourcenodes connected downstream — these would be pitched up and down according to the relative speed of the pannernode and the audiolistener.

GeolocationCoordinates - Web APIs
if speed is 0, heading is nan.
... geolocationcoordinates.speed read only secure context returns a double representing the velocity of the device in meters per second.

HTMLMediaElement.defaultPlaybackRate - Web APIs
syntax var dspeed = video.defaultplaybackrate; audio.defaultplaybackrate = 1.0; value a double.
... 1.0 is "normal speed," values lower than 1.0 make the media play slower than normal, higher values make it play faster.

HTMLMediaElement - Web APIs
if set to false, the pitch will adjust to the speed of the audio.
...this non-standard, experimental method makes it possible to manually drive reading and rendering of media at a custom speed, or to move through the media frame-by-frame to perform filtering or other operations.

Using IndexedDB - Web APIs
you can speed up data access by using the right scope and mode in the transaction.
... note that you can speed up data access by limiting the scope and mode in the transaction.

MediaPositionState.playbackRate - Web APIs
a value of 1.0 indicates the media is playing forward at normal speed, while higher values indicate that the media is being played faster than normal.
... example in this example, an app is updating the browser to let it know that the user has clicked a button causing the playback to shift to a double-speed mode.

MediaSession.setPositionState() - Web APIs
the mediasession method setpositionstate() is used to update the current document's media playback position and speed for presentation by user's device in any kind of interface that provides details about ongoing media.
... syntax navigator.mediasession.setpositionstate(statedict); parameters statedict optional an object conforming to the mediapositionstate dictionary, providing updated information about the playback position and speed of the document's ongoing media.

NetworkInformation.downlinkMax - Web APIs
the networkinformation.downlinkmax read-only property returns the maximum downlink speed, in megabits per second (mbps), for the underlying connection technology.
... syntax var max = networkinformation.downlinkmax return value an unrestricted double representing the maximum downlink speed, in megabits per second (mb/s), for the underlying connection technology.

PerformanceTiming.domInteractive - Web APIs
this property can be used to measure the speed of loading web sites that users feels.
...check if you are in one of these cases before using this property as a proxy for the user experience of a web site's speed of loading.

Matrix math for the web - Web APIs
et's look at this function in action: let somematrix = [ 4, 0, 0, 0, 0, 3, 0, 0, 0, 0, 5, 0, 4, 8, 4, 1 ] let identitymatrix = [ 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1 ]; // returns a new array equivalent to somematrix let somematrixresult = multiplymatrices(identitymatrix, somematrix); important: these matrix functions are written for clarity of explanation, not for speed or memory management.
...glmatrix is an example of a library that has a focus on speed and performance.

Rendering and the WebXR frame animation callback - Web APIs
for that reason, you need to use the timestamp provided to ensure your animation renders at precisely the desired speed.
... the same concept applied for objects that are moving rather than simply rotating: const xdistancemoved = xspeedpersecond * deltatime; const ydistancemoved = yspeedpersecond * deltatime; const zdistancemoved = zspeedpersecond * deltatime; xspeedpersecond, yspeedpersecond, and zspeedpersecond each contian that axis's component of the object's velocity.

Web Animations API Concepts - Web APIs
all the animation's playback relies on this timeline: seeking the animation moves the animation’s position along the timeline; slowing down or speeding up the playback rate condenses or expands its spread across the timeline; repeating the animation lines up additional iterations of it along the timeline.
...like a dvd player, we can use the animation object’s methods to play, pause, seek, and control the animation’s playback direction and speed.

Advanced techniques: Creating and sequencing audio - Web APIs
the interface consists of master controls, which allow us to play/stop the sequencer, and adjust the bpm (beats per minute) to speed up or slow down the "music".
...let's expose that to our ui, so we can speed up and slow down our sample.

position - CSS: Cascading Style Sheets
depending on the content needing to be repainted, the browser performance, and the device's processing speed, the browser may not be able to manage repaints at 60 fps, causing accessibility concerns for people with sensitivities and jank for everyone.
... one solution is to add will-change: transform to the positioned elements to render the element in its own layer, improving repaint speed and therefore improving performance and accessibility.

Web Audio playbackRate explained - Developer guides
the playbackrate property of the <audio> and <video> elements allows us to change the speed, or rate, at which a piece of web audio or video is playing.
...next we set playbackrate to 0.5, which represents half normal speed (the playbackrate is a multiplier applied to the original rate.) a complete example let's create a <video> element first, and set up video and playback rate controls in html: <video id="myvideo" controls> <source src="https://udn.realityripple.com/samples/6f/08625b424a.m4v" type='video/mp4' /> <source src="https://udn.realityripple.com/samples/5b/8cd6da9c65.webm" type='video/webm' /> </video...

Audio and video manipulation - Developer guides
playbackrate is a number that represents a multiple to be applied to the rate of playback, for example 0.5 represents half speed while 2 represents double speed.
... note that the playbackrate property works with both <audio> and <video>, but in both cases, it changes the playback speed but not the pitch.

Using the application cache - HTML: Hypertext Markup Language
speed cached resources are local, and therefore load faster.
...this speeds up the document load time.

Web audio codec guide - Web media technologies
this is necessary because the rate at which the music is downloaded needs to be no greater than the amount of bandwidth available on the network, and ideally there should be room left for network speed fluctuations and use of the network by other applications.
... example: music for download music being downloaded by the user can be compressed to a larger overall file size than streamed music, since (unlike when streaming) it doesn't matter if the download speed is slower than the playback speed of the media.

Web video codec guide - Web media technologies
wagon-wheel effect the wagon-wheel effect (or stroboscopic effect) is the visual effect that's commonly seen in film, in which a turning wheel appears to rotate at the wrong speed, or even in reverse, due to an interaction between the frame rate and the compression algorithm.
...this is a temporal (time-based) aliasing issue; the speed of the rotation interferes with the frequency of the sampling performed during compression or encoding.

Performance fundamentals - Web Performance
but often trading some generality and quality for speed, such as using a static rendering instead of a css radial gradient, can push scrolling framerate over a target.
... memory and power usage improving memory and power usage is a similar problem to speeding up startup: don't do unneeded work or lazily load uncommonly-used ui resources.

Performance budgets - Web Performance
pagespeed index, lighthouse score).
... in order to begin, you need to first measure the devices and connection speeds where your users are coming from (e.g.

WebAssembly Concepts - WebAssembly
this has huge implications for the web platform — it provides a way to run code written in multiple languages on the web at near-native speed, with client apps running on the web that previously couldn’t have done so.
... webassembly goals webassembly is being created as an open standard inside the w3c webassembly community group with the following goals: be fast, efficient, and portable — webassembly code can be executed at near-native speed across different platforms by taking advantage of common hardware capabilities.

lang/functional - Archive of obsolete content
useful for speeding up slow-running computations.

Chapter 6: Firefox extensions and XUL applications - Archive of obsolete content
it should be very easy for java programmers to get up to speed on it quickly.

Chapter 5: Let's build a Firefox extension - Archive of obsolete content
preference description value nglayout.debug.disable_xul_cache (not present in firefox 3.5+) ordinarily, firefox will cache xul documents after they have been read in once, to speed subsequent displays.

Performance best practices in extensions - Archive of obsolete content
this article offers some best practices and suggestions that can not only improve the performance and speed of your extension, but also of firefox itself.

Add-ons - Archive of obsolete content
this article offers some best practices and suggestions that can not only improve the performance and speed of your extension, but also of firefox itself.

An Interview With Douglas Bowman of Wired News - Archive of obsolete content
can you see an advantage to reducing file size and speeding up download time?

Index - Archive of obsolete content
luding those with learning disabilities, cognitive disabilities, or people who are deaf." 3818 the business benefits of web standards needsupdate, web development, web standards doing more with less seems to be the mission impossible for web designers: addressing more customers, a broader audience, more diversity in terms of browsers, more accessibility, users asking for more speed, while spending less to maintain or redesign a web site.

Inner-browsing extending the browser navigation paradigm - Archive of obsolete content
on slow speed connections, this process can be slow and frustrating.

MMgc - Archive of obsolete content
this could be a significant speedup if the black object was a large array getting populated with a bunch of new objects.

Notes on HTML Reflow - Archive of obsolete content
were we to process each individually, the text widget would be flowed once for each keystroke, which would be wasteful if the latency of an individual reflow exceeds the speed at which text is being typed.

Source Navigator - Archive of obsolete content
now you can enjoy searching the mozilla code in a faster speed.

Creating a hybrid CD - Archive of obsolete content
mkhybrid -o ~/party.iso -r -j -hfs -v mozilla.party -map ~/hfsmapping ~/party/ cdrecord -v speed=2 dev=0,6,0 ~/party.iso its also handy to be able to mount an image file to test it.

Download Manager improvements in Firefox 3 - Archive of obsolete content
examples monitoring downloads an example showing how to use the new download manager apis to create a download log window that shows all past and present downloads and their status, including the start and end times of the downloads, the download speed, and more.

Style System Overview - Archive of obsolete content
some style data is cached on nsrulenode objects to speed up computation and reduce memory use.

Running Tamarin acceptance tests - Archive of obsolete content
notes on using acceptance runtests.py threading in order to speed up the execution time of the acceptance testsuite, the runtests script automatically detects the number of cores on the machine and sets an equivalent number of threads.

Running Tamarin performance tests - Archive of obsolete content
results from the two shells will be shown side to side and the percent speedup will be shown.

Using addresses of stack variables with NSPR threads on win16 - Archive of obsolete content
with the speed of today's processors (even those running win-16), the copying of 10 - 50 kilobytes of data between two locations in memory is barely measurable 1.

Example Sticky Notes - Archive of obsolete content
it also speeds up the parsing as the engine doesn't go through cdata sections but simply skip on them.

Building Menus With Templates - Archive of obsolete content
note that the generated content does not get removed again when the menu is closed again; this extra feature of menus is only intended to be a performance enhancement to speed up the time it takes to display a window by avoiding extra generation that can be put off until later.

Complete - Archive of obsolete content
it is normally uncompressed, trading off some disk space for speed.

Advanced Rules - Archive of obsolete content
for example, in the example above, we might want to check for the temperature and the wind speed.

More Event Handlers - Archive of obsolete content
this is because the mousemove events occur at intervals depending on the speed at which the mouse moves and the mouse is usually moved some distance past the border by the time the next event fires.

XUL accessibility tool - Archive of obsolete content
be aware that the report might take a little while to be ready depending on the complexity of the application being analyzed and the speed of your machine.

XML - Archive of obsolete content
any familiarity you already have with xml will help you quickly get up to speed developing with xul.

Using SOAP in XULRunner 1.9 - Archive of obsolete content
xulrunner 1.8.* - using an old xulrunner is certainly an option but brings up a host of speed, stability and memory issues.

Mozilla release FAQ - Archive of obsolete content
it features speed improvements, a more modular nature, and significantly less platform-dependant code.

2006-10-06 - Archive of obsolete content
also invites people to help extension developers test for compatibility (link to a bunch of extension compatability bugs) discussions reining in the release process a discussion of what can be done to speed up the release process.

2006-10-13 - Archive of obsolete content
sunbird and lighting 0.3 sunbird and lighting 0.3 were released on october 11 discussions release process discussion discussion from last week regarding speeding up and automation of the release process continued.

Introduction to SSL - Archive of obsolete content
decisions about which cipher suites a particular organization decides to enable depend on trade-offs among the sensitivity of the data involved, the speed of the cipher, and the applicability of export rules.

Using the W3C DOM - Archive of obsolete content
useful references on changing an element's text using the dom whitespace in the dom by david baron element.innerhtml speed and performance comparison between innerhtml attribute and dom's nodevalue when modifying the text data of a text node by gérard talbot interactive dom level 2 characterdata interface attributes and methods tests: other ways to modify (replace, delete, manipulate) efficiently text nodes in the dom by gérard talbot <- previous section: using web standards: how next section: developing cros...

MSX Emulator (jsMSX) - Archive of obsolete content
they present an interesting testbed for pushing the current javascript implementations to their limits and for comparing their relative speed.

Server-Side JavaScript - Archive of obsolete content
now, with tracemonkey available, javascript (both client side and server-side) can see 20x to 40x speed improvements according to brendan eich, mozilla cto and creator of javascript.

Anatomy of a video game - Game development
systems that are unable to keep up with 60 fps lose visual quality to keep the game running at optimal speed (eventually it outright fails, if quality becomes too low.) other ways to handle variable refresh rate needs other methods of tackling the problem exist.

Game distribution - Game development
bear in mind that downloading the game might still take a bit of time depending on the size of the game and your network speed.

Building up a basic demo with Babylon.js - Game development
to speed up development babylon.js provides a bunch of predefined primitives that you can use to create shapes instantly in a single line of code.

Building up a basic demo with the PlayCanvas engine - Game development
to speed up development playcanvas provides a bunch of predefined primitives that you can use to create shapes instantly in a single line of code.

Building up a basic demo with Three.js - Game development
to speed up development, three.js provides a bunch of predefined primitives, which you can use to create shapes instantly in a single line of code.

GLSL Shaders - Game development
to speed up the background code we will be using the three.js api.

3D games on the Web - Game development
the rise of libraries and frameworks coding raw webgl is fairly complex, but you'll want to get to grips with it in the long run, as your projects get more advanced (see our webgl documentation to get started.) for real-world projects you'll probably also make use of a framework to speed up development and help you manage the project you're working on.

Audio for Web games - Game development
using the playbackrate() method you can even adjust the speed of your music without affecting the pitch, to sync it up better with the action.

Tools for game development - Game development
gecko profiler the gecko profiler extension lets you profile your code to help figure out where your performance issues are so that you can make your game run at top speed.

Bounce off the walls - Game development
if the ball was moving upwards with a speed of 2 pixels per frame, now it will be moving "up" with a speed of -2 pixels, which actually equals to moving down at a speed of 2 pixels per frame.

Move the ball - Game development
, y, 10, 0, math.pi*2); ctx.fillstyle = "#0095dd"; ctx.fill(); ctx.closepath(); } function draw() { ctx.clearrect(0, 0, canvas.width, canvas.height); drawball(); x += dx; y += dy; } compare your code you can check the finished code for this article for yourself in the live demo below, and play with it to understand better how it works: exercise: try changing the speed of the moving ball, or the direction it moves in.

2D breakout game using pure JavaScript - Game development
frameworks speed up development time and help take care of boring parts of the game, but if something is not working as expected, you can always try to debug that or just write your own solutions in pure javascript.

2D breakout game using Phaser - Game development
frameworks speed up development time and help take care of the boring parts, allowing you to concentrate on the fun stuff.

Gecko FAQ - Gecko Redirect 1
gecko technologies will also power the display of the mozilla.com portal site, speedily delivering more exciting content and services.

Delta - MDN Web Docs Glossary: Definitions of Web-related terms
the term delta is commonly used when communicating changes in speed, position, or acceleration of a physical or virtual object.

frame rate (FPS) - MDN Web Docs Glossary: Definitions of Web-related terms
a frame rate is the the speed at which the browser is able to recalculate, layout and paint content to the display.

First input delay - MDN Web Docs Glossary: Definitions of Web-related terms
the time between when content is painted to the page and when all the functionality becomes responsive to human interaction often varies based on the the size and complexity of the javascript needing to be downloaded, parsed, and executed on the main thread, and on the device speed or lack thereof (think low end mobile devices).

Gzip compression - MDN Web Docs Glossary: Definitions of Web-related terms
learn more how to enable compression and gzip for page speed.

Perceived performance - MDN Web Docs Glossary: Definitions of Web-related terms
speed index is a common metric for measuring perceived performance, though it's not perfect.

Prefetch - MDN Web Docs Glossary: Definitions of Web-related terms
they are most relevant when there are a plethora of links to external websites that may be clicked on, like search engine results, dns prefetching resolves domain names in advance thereby speeding up load times by reducing the time associated with domain lookup at request time.

UDP (User Datagram Protocol) - MDN Web Docs Glossary: Definitions of Web-related terms
udp (user datagram protocol) is a long standing protocol used together with ip for sending data when transmission speed and efficiency matter more than security and reliability.

VoIP - MDN Web Docs Glossary: Definitions of Web-related terms
a high speed internet connection is required for voip.

Brotli - MDN Web Docs Glossary: Definitions of Web-related terms
brotli provides better compression ratios than gzip and deflate speeds are comparable, but brotli compressing is a slower process than gzip compression, so gzip may be a better option for the compression of non-cachable content.

MDN Web Docs Glossary: Definitions of Web-related terms
simd simple header simple response header sisd site site map sld sloppy mode slug smoke test smpte (society of motion picture and television engineers) smtp snap positions soap spa (single-page application) specification speculative parsing speed index sql sql injection sri stacking context state machine statement static method static typing strict mode string stun style origin stylesheet svg svn symbol symmetric-key cryptography synchronous syntax syntax error ...

What is accessibility? - Learn web development
other good practices that improve accessibility also make your site more usable by other groups, such as mobile phone users or those on low network speed.

Installing basic software - Learn web development
libraries, frameworks, etc., to speed up writing common functionality.

Tips for authoring fast-loading HTML pages - Learn web development
this not only speeds the display of the page but prevents annoying changes in a page's layout when the page completes loading.

Use JavaScript within a webpage - Learn web development
people may have javascript turned off to improve speed and security, and users often face network issues that prevent loading scripts.

Index - Learn web development
what users, browsers, and devices do you most need to worry about?), how to go about doing testing, the main issues that you'll face with different types of code and how to mitigate them, what tools are most useful in helping you test and fix problems, and how to use automation to speed up testing.

Drawing graphics - Learn web development
the browser works out complex details such as making the animation run at a consistent speed, and not wasting resources animating things that can't be seen.

Fetching data from the server - Learn web development
to speed things up even further, some sites also store assets and data on the user's computer when they are first requested, meaning that on subsequent visits they use the local versions instead of downloading fresh copies when the page is first loaded.

Introduction to web APIs - Learn web development
javascript libraries — usually one or more javascript files containing custom functions that you can attach to your web page to speed up or enable writing common functionality.

What is web performance? - Learn web development
performance measurements: web performance involves measuring the actual and perceived speeds of an application, optimizing where possible, and then monitoring the performance, to ensure that what you've optimized stays optimized.

Multimedia: video - Learn web development
consider streaming video streaming allows the proper video size and bandwidth (based on network speed) to be delivered to the end user.

Implementing feature detection - Learn web development
this article details how to write your own simple feature detection, how to use a library to speed up implementation, and native features for feature detection such as @supports.

Client-side tooling overview - Learn web development
although it is still entirely reasonable to write html, css, and javascript "by hand" there is now a wealth of tools that developers can use to speed up the process of building a web site, or app.

Tools and testing - Learn web development
what users, browsers and devices do you most need to worry about?), how to go about testing, the main issues that you'll face with different types of code and how to fix/mitigate those, what tools are most useful in helping you test and fix problems, and how to use automation to speed up testing.

Mozilla accessibility architecture
returning nothing for leaf and text objects also helps speed up tree construction and traversal.

Embedding API for Accessibility
setboolpref("browser.accept.video", acceptvideo); no audio setboolpref("browser.accept.audio", acceptaudio); no timed events setboolpref("browser.accept.timed_events", accepttimedevents); no timer speed setintpref("timer.relative_speed", percent); /* 100 corresponds to normal speed, 200 to double speed */ no allow cycling in lists and links setboolpref("keyboardnav.allow_cycling", allowcycling); no mouse pointer moves with keyboard focus ...

Simple SeaMonkey build
high speed internet installing build tools if your system is not listed below, see the build prerequisites page.

SVG Guidelines
you can avoid this by doing basic algebra, for example: <g transform="translate(-62, -310)"><shape transform="translate(60, 308)"/></g> can be cut down to: <shape transform="translate(-2,-2)"/> because: -62+60 = -310+308 = -2 performance tips these rules are optional, but they help speeding up the svg.

How Mozilla determines MIME Types
sexternalhelperappservice.cpp) the file->mime type mapping works like this: on beos, the operating system is asked for the type of the file (not quite yet, bug 217723) on macos, the type and creator code will be used to lookup the type of the file from the os a hardcoded list of extensions is checked (containing currently 13 entries, nsexternalhelperappservice.cpp line 463 (this is done for speed – it is faster to find data in the hardcoded list than asking the os or looking in preferences) if the extension is not listed there, it becomes interesting.

How to get a stacktrace with WinDbg
this may take some time depending on your connection speed; the total size of the mozilla and microsoft symbols download is around 1.4gb.

OSFile.jsm
depending on the current load of the kernel, the current disk activity, the current load of the bus, the current rotation speed of the disk, the amount of battery power, etc.

Translation phase
these are the mozilla application projects that are localized using the l10n tools above: firefox the award-winning firefox® web browser has security, speed and new features that will change the way you use the web.

Localization sign-off reviews
using these colors helps us to identify potential bugs and approve your latest revision with speed while maintaining critical accuracy.

Power profiling overview
in the context of computing, a fully-charged mobile device battery (as found in a laptop or smartphone) holds a certain amount of energy, and the speed at which that stored energy is depleted depends on the power consumption of the mobile device.

Emscripten
emscripten generates fast code — its default output format is asm.js , a highly optimizable subset of javascript that can execute at close to native speed in many cases.

Hash Tables
a hash table lookup may change the internal organization of the hash table (to speed up future lookups).

PLHashTable
the number of buckets in a hash table may be changed by the library functions during the lifetime of the table to optimize speed and space.

An overview of NSS Internals
this strategy allows nss to work with many hardware devices (e.g., to speed up the calculations required for cryptographic operations, or to access smartcards that securely protect a secret key) and software modules (e.g., to allow to load such modules as a plugin that provides additional algorithms or stores key or trust information) that implement the pkcs#11 interface.

Index
this strategy allows nss to work with many hardware devices (e.g., to speed up the calculations required for cryptographic operations, or to access smartcards that securely protect a secret key) and software modules (e.g., to allow to load such modules as a plugin that provides additional algorithms or stores key or trust information) that implement the pkcs#11 interface.

NSS 3.48.1 release notes
bugs fixed in nss 3.48.1 bug 1606992 - cache the most recent pbkdf2 password hash, to speed up repeated sdr operations, important with the increased kdf iteration counts.

NSS 3.49.1 release notes
bugs fixed in nss 3.49.1 bug 1606992 - cache the most recent pbkdf2 password hash, to speed up repeated sdr operations, important with the increased kdf iteration counts.

NSS 3.49.2 release notes
bugs fixed in nss 3.49.2 bug 1606992 - cache the most recent pbkdf1 password hash, to speed up repeated sdr operations, important with the increased kdf iteration counts.

NSS 3.50 release notes
bugs fixed in nss 3.50 bug 1599514 - update dtls 1.3 implementation to draft-30 bug 1603438 - fix native tools build failure due to lack of zlib include dir if external bug 1599603 - nist sp800-108 kbkdf - pkcs#11 implementation bug 1606992 - cache the most recent pbkdf1 password hash, to speed up repeated sdr operations, important with the increased kdf iteration counts.

NSS 3.53 release notes
notable changes in nss 3.53 when using the makefiles, nss can be built in parallel, speeding up those builds to more similar performance as the build.sh/ninja/gyp system.

nss tech note1
this feature will most likely never be added, as this decoder gets most of its extra speed from not making a copy of the input data, which would be required when streaming.

NSS_Initialize
nss_init_optimizespace - optimize for space instead of speed.

Performance Hints
not only is it good programming practice, it can speed up your code by allowing the compiler to generate special code to access the variables.

Shumway
note: if your applet runs at an abnormal speed, try toggling "turbo" at the bottom of the inspector window.

Creating JavaScript tests
it is not generally even possible to tell if the speed of any particular feature is going to be important in the real world without running a real-world benchmark.

Functions
flat closures and null closures have been removed: https://bugzilla.mozilla.org/show_bug.cgi?id=730497 https://bugzilla.mozilla.org/show_bug.cgi?id=739808 name lookups in order of speed, fastest to slowest.

SpiderMonkey Internals: Thread Safety
this allows allocation to avoid locking most of the time (a significant speed win).

Tracing JIT
running backwards sometimes makes the logic difficult to follow, but it is an essential factor in maintaining the assembler's high speed and small size.

JIT Optimization Outcomes
spidermonkey's optimizing jit, ionmonkey, uses different optimization strategies to speed up various operations.

JIT Optimization Strategies
it provides information on what they attempt to do, what general level of speed-up they provide, what kind of program characteristics can prevent them from being used, and common ways to enable the engine to utilize that optimization.

SpiderMonkey 1.8.5
spidermonkey 1.8.5 includes a just-in-time compiler (jit) (several, actually) that compiles javascript to machine code, for a significant speed increase.

SpiderMonkey 1.8.7
spidermonkey 1.8.7 includes type inference, which boosts the speed of the jägermonkey jit by about 30% over version 1.8.5.

SpiderMonkey 1.8.8
spidermonkey 1.8.8 includes a just-in-time compiler (jit) that compiles javascript to machine code, for a significant speed increase.

SpiderMonkey 17
spidermonkey 17 includes a just-in-time compiler (jit) that compiles javascript to machine code, for a significant speed increase.

SpiderMonkey 24
spidermonkey 24 includes a just-in-time compiler (jit) that compiles javascript to machine code, for a significant speed increase.

SpiderMonkey 31
spidermonkey 31 includes a just-in-time compiler (jit) that compiles javascript to machine code, for a significant speed increase.

SpiderMonkey 38
spidermonkey 38 includes a just-in-time compiler (jit) that compiles javascript to machine code, for a significant speed increase.

SpiderMonkey 45
spidermonkey 45 includes a just-in-time compiler (jit) that compiles javascript to machine code, for a significant speed increase.

Running Automated JavaScript Tests
thus, you can keep retesting as you fix bugs and only the tests that failed the last time will run, speeding things up a bit.

Redis Tips
the speed benefits of redis are lost when you overflow into disk memory.

Avoiding leaks in JavaScript XPCOM components
(the implementation is slightly more complicated, but only to optimize for speed and reduce creation and destruction of wrapper objects.) the wrapper object is reference counted, and as long as it exists, it makes the javascript object that it wraps be one of the roots used by the javascript garbage collector's mark phase.

Components.Constructor
nces of a component in many different places): var bis = components.classes["@mozilla.org/binaryinputstream;1"] .createinstance(components.interfaces.nsibinaryinputstream); bis.setinputstream(someinputstream); // assumes binaryinputstream was initialized previously var bis = new binaryinputstream(someinputstream); components.constructor() is purely syntactic sugar (albeit speedy and pretty syntactic sugar) for actions that can be accomplished using other common methods.

mozIStorageConnection
this preload operation can dramatically speed up read operations because the data is loaded as one large block.

nsIDOMGeoPositionCoords
speed double the speed at which the user is moving, in meters per second (confirm this).

nsIDownload
speed double the downloads transfer speed in bytes per second.

nsIMsgDatabase
void getnewlist(out unsigned long count, [array, size_is(count)] out nsmsgkey newkeys); getcachedhits() these are used for caching search hits in a database, to speed up saved search folders.

Performance
these disk syncs are very slow and limit the speed of a commit to the rotational speed of the mechanical disk.

Xptcall Porting Guide
please remember that safety and reliability are more important than speed optimizations.

Mozilla
some of them are simply the ones i use because i like them, while others are scripts that i've created to speed up the work.

Accessibility Inspector - Firefox Developer Tools
this means trying your best to not lock anyone out of accessing information because of any disability they may have, or any other personal circumstances such as the device they are using, the speed of their network connection, or their geographic location or locale.

Index - Firefox Developer Tools
53 throttling 110n:priority, debugging, dev tools, firefox, guide, networking, tools the network monitor allows you to throttle your network speed to emulate various connection speeds so you can see how your app will behave under different connection types.

Animation.playbackRate - Web APIs
e, false); cake.addeventlistener("touchstart", growalice, false); in another example, the red queen's race game, alice and the red queen are constantly slowing down: setinterval( function() { // make sure the playback rate never falls below .4 if (redqueen_alice.playbackrate > .4) { redqueen_alice.playbackrate *= .9; } }, 3000); but clicking or tapping on them causes them to speed up by multiplying their playbackrate: var gofaster = function() { redqueen_alice.playbackrate *= 1.1; } document.addeventlistener("click", gofaster); document.addeventlistener("touchstart", gofaster); specifications specification status comment web animationsthe definition of 'animation.playbackrate' in that specification.

Animation - Web APIs
animation.updateplaybackrate() sets the speed of an animation after first synchronizing its playback position.

AudioBufferSourceNode.start() - Web APIs
the computation of the offset into the sound is performed using the sound buffer's natural sample rate, rather than the current playback rate, so even if the sound is playing at twice its normal speed, the midway point through a 10-second audio buffer is still 5.

Detecting device orientation - Web APIs
the motion event contains four properties: devicemotionevent.acceleration devicemotionevent.accelerationincludinggravity devicemotionevent.rotationrate devicemotionevent.interval motion values explained the devicemotionevent objects provide web developers with information about the speed of changes for the device's position and orientation.

DeviceMotionEvent - Web APIs
the devicemotionevent provides web developers with information about the speed of changes for the device's position and orientation.

Document: scroll event - Web APIs
// reference: http://www.html5rocks.com/en/tutorials/speed/animations/ let last_known_scroll_position = 0; let ticking = false; function dosomething(scroll_pos) { // do something with the scroll position } window.addeventlistener('scroll', function(e) { last_known_scroll_position = window.scrolly; if (!ticking) { window.requestanimationframe(function() { dosomething(last_known_scroll_position); ticking = false; }); tick...

EffectTiming.easing - Web APIs
ease-in-out this rate of change speeds up in the middle.

Element: DOMMouseScroll event - Web APIs
note: if the platform's native mouse wheel events only provide scroll distance by pixels, or if the speed can be customized by the user, the value is computed using the line height of the nearest scrollable ancestor element of the event's target.

Element: scroll event - Web APIs
// reference: http://www.html5rocks.com/en/tutorials/speed/animations/ let last_known_scroll_position = 0; let ticking = false; function dosomething(scroll_pos) { // do something with the scroll position } window.addeventlistener('scroll', function(e) { last_known_scroll_position = window.scrolly; if (!ticking) { window.requestanimationframe(function() { dosomething(last_known_scroll_position); ticking = false; }); tick...

Introduction to the File and Directory Entries API - Web APIs
audio or photo editor with offline access or local cache (great for performance and speed) the app can write to files in place (for example, overwriting just the id3/exif tags and not the entire file).

GeolocationCoordinates.heading - Web APIs
if geolocationcoordinates.speed is 0, heading is nan.

GeolocationPosition.coords - Web APIs
it contains the location, that is longitude and latitude on the earth, the altitude, and the speed of the object concerned, regrouped inside the returned value.

GeolocationPosition - Web APIs
the position, represented by a geolocationcoordinates object, comprehends the 2d position of the device, on a spheroid representing the earth, but also its altitude and its speed.

Using the Geolocation API - Web APIs
hence many geolocation success callbacks look fairly simple: function success(position) { const latitude = position.coords.latitude; const longitude = position.coords.longitude; // do something with your latitude and longitude } you can however get a number of other bits of information from a geolocationcoordinates object, including altitude, speed, what direction the device is facing, and an accuracy measure of the altitude, longitude, and latitude data.

HTMLCanvasElement.getContext() - Web APIs
if set to false, the browser now knows that the backdrop is always opaque, which can speed up drawing of transparent content and images.

LocalFileSystem - Web APIs
for example, if you were to create a mail app, you might create a temporary storage for caching assets (like images and attachments) to speed up performance, while creating persistent storage for unique data—such as drafts of emails that were composed while offline—that should not be lost before they are backed up into the cloud.

MediaSession - Web APIs
setpositionstate() sets the current playback position and speed of the media currently being presented.

Media Session API - Web APIs
mediapositionstate used to contain information about the current playback position, playback speed, and overall media duration when calling the mediasession method setpositionstate() to establish the media's length, playback position, and playback speed.

NetworkInformation - Web APIs
networkinformation.downlinkmax read only returns the maximum downlink speed, in megabits per second (mbps), for the underlying connection technology.

Network Information API - Web APIs
regardless of the type value you can get an estimate of connection speed through the networkinformation.effectivetype property.

OffscreenCanvas.getContext() - Web APIs
if set to false, the browser now knows that the backdrop is always opaque, which can speed up drawing of transparent content and images then.

PannerNode.setVelocity() - Web APIs
the velocity relative to the listener is used to control the pitch change needed to conform with the doppler effect due to the relative speed.

RTCRemoteOutboundRtpStreamStats - Web APIs
be aware that the remote clock may not be synchronized with the local clock (either in current time or speed at which time elapses).

ReadableStream.tee() - Web APIs
this is useful for allowing two readers to read a stream simultaneously, perhaps at different speeds.

format - Web APIs
ring font format examples of common extensions truedoc-pfr truedoc™ portable font resource .pfr embedded-opentype embedded opentype .eot type-1 postscript™ type 1 .pfb, .pfa truetype truetype .ttf opentype opentype, including truetype open .ttf truetype-gx truetype with gx extensions - speedo speedo - intellifont intellifont - example myglyph.format = "truedoc-pfr"; specifications specification status comment scalable vector graphics (svg) 1.1 (second edition)the definition of 'format' in that specification.

SpeechSynthesisUtterance.rate - Web APIs
the rate property of the speechsynthesisutterance interface gets and sets the speed at which the utterance will be spoken at.

SpeechSynthesisUtterance - Web APIs
speechsynthesisutterance.rate gets and sets the speed at which the utterance will be spoken at.

Streams API concepts - Web APIs
backpressure an important concept in streams is backpressure — this is the process by which a single stream or a pipe chain regulates the speed of reading/writing.

Streams API - Web APIs
there are more advantages too — you can detect when streams start or end, chain streams together, handle errors and cancel streams as required, and react to the speed of the stream is being read at.

TextEncoder.prototype.encodeInto() - Web APIs
if the output is expected to be long-lived, it makes sense to compute minimum allocation rounduptobucketsize(s.length), the maximum allocation size s.length * 3, and to have a chosen (as a tradeoff between memory usage and speed) threshold t such that if rounduptobucketsize(s.length) + t >= s.length * 3, you simply allocate for s.length * 3.

A basic 2D WebGL animation example - Web APIs
then the current rotation angle (in degrees) is set to 0.0, since we haven't performed any rotation yet, and the rotation speed (in degrees per screen refresh period, typically 60 fps) is set to 6.

WebGL best practices - Web APIs
consider rendering to a smaller backbuffer size a common (and easy) way to trade off quality for speed is rendering into a smaller backbuffer, and upscaling the result.

Using the Web Animations API - Web APIs
we use updateplaybackrate() instead of setting the playbackrate directly since that produces a smooth update: setinterval( function() { // make sure the playback rate never falls below .4 if (redqueen_alice.playbackrate > .4) { redqueen_alice.updateplaybackrate(redqueen_alice.playbackrate * .9); } }, 3000); but urging them on by clicking or tapping causes them to speed up by multiplying their playbackrate: var gofaster = function() { redqueen_alice.updateplaybackrate(redqueen_alice.playbackrate * 1.1); } document.addeventlistener("click", gofaster); document.addeventlistener("touchstart", gofaster); the background elements also have playbackrates that are impacted when you click or tap.

Window.open() - Web APIs
do not use target="_blank" always provide a meaningful name to your target attribute and try to reuse such target attribute in your page so that a click on another link may load the referenced resource in an already created and rendered window (therefore speeding up the process for the user) and therefore justifying the reason (and user system resources, time spent) for creating a secondary window in the first place.

Window.requestAnimationFrame() - Web APIs
the element moves at a speed of 0.1px/ms to the right, so its relative position (in css pixels) can be calculated in function of the time elapsed since the start of the animation (in milliseconds) with 0.1 * elapsed.

XRReferenceSpace.getOffsetReferenceSpace() - Web APIs
let mouseyaw = 0.0; let mousepitch = 0.0; const inverseorientation = quat.create(); const mouse_speed = 0.003; function rotateviewby(dx, dy) { mouseyaw += dx * mouse_speed; mousepitch += dy * mouse_speed; if (mousepitch < -math.pi * 0.5) { mousepitch = -math.pi * 0.5; } else if (mousepitch > math.pi * 0.5) { mousepitch = math.pi * 0.5; } } finally, we need code that actually applies the computed yaw and pitch to the viewer's orientation.

Accessibility: What users can do to browse more safely - Accessibility
they can be addressed by the design and speed of the display and computer" hardware and operating systems on many computers offer control that is not afforded to developers.

An overview of accessible web applications and widgets - Accessibility
implementing desktop-style keyboard conventions on the web has the potential to significantly speed up navigation for many users.

Cognitive accessibility - Accessibility
cognitive skills include: attention memory processing speed time management letters and language numbers symbols and math understanding and making choices a solid approach to providing accessible solutions for people with cognitive impairments includes: delivering content in more than one way, such as by text-to-speech or by video; providing easily-understood content, such as text written using plain-language standards; focusing attention on im...

-webkit-overflow-scrolling - CSS: Cascading Style Sheets
the speed and duration of the continued scrolling is proportional to how vigorous the scroll gesture was.

update - CSS: Cascading Style Sheets
fast the layout may change dynamically according to the usual rules of css, and the output device is not unusually constrained in speed, so regularly-updating things like css animations can be used.

Relationship of flexbox to other layout methods - CSS: Cascading Style Sheets
as css became a more feature rich language, maintaining one huge specification became problematic, with different parts of css moving on at different speeds.

CSS Images - CSS: Cascading Style Sheets
implementing image sprites in css describes the common technique grouping several images in one single document to save download requests and speed up the availability of a page.

Using CSS transitions - CSS: Cascading Style Sheets
css transitions provide a way to control animation speed when changing css properties.

WebKit CSS extensions - CSS: Cascading Style Sheets
-locale -webkit-logical-height -webkit-logical-width m -webkit-margin-after-collapse -webkit-margin-after -webkit-margin-before-collapse -webkit-margin-before -webkit-margin-bottom-collapse -webkit-margin-collapse -webkit-margin-end** -webkit-margin-start** -webkit-margin-top-collapse -webkit-marquee-direction -webkit-marquee-increment -webkit-marquee-repetition -webkit-marquee-speed -webkit-marquee-style -webkit-marquee -webkit-mask-box-image-outset -webkit-mask-box-image-repeat -webkit-mask-box-image-slice -webkit-mask-box-image-source -webkit-mask-box-image-width -webkit-mask-box-image -webkit-mask-repeat-x -webkit-mask-repeat-y -webkit-mask-source-type -webkit-max-logical-height -webkit-max-logical-width -webkit-min-logical-height -webkit-min-logical-width ...

<alpha-value> - CSS: Cascading Style Sheets
the speed of the interpolation is determined by the timing function associated with the animation.

<color> - CSS: Cascading Style Sheets
in animations, the interpolation's speed is determined by the timing function.

image-rendering - CSS: Cascading Style Sheets
note: the values optimizequality and optimizespeed present in an early draft (and coming from its svg counterpart image-rendering) are defined as synonyms for the smooth and pixelated values respectively.

<integer> - CSS: Cascading Style Sheets
the speed of the interpolation is determined by the timing function associated with the animation.

<length> - CSS: Cascading Style Sheets
the speed of the interpolation is determined by the timing function associated with the animation.

<number> - CSS: Cascading Style Sheets
the speed of the interpolation is determined by the timing function associated with the animation.

<percentage> - CSS: Cascading Style Sheets
the speed of the interpolation is determined by the timing function associated with the animation.

<position> - CSS: Cascading Style Sheets
however, because the speed of the interpolation is determined by a single timing function for both coordinates, the point will move in a straight line.

<shape> - CSS: Cascading Style Sheets
the speed of the interpolation is determined by the timing function associated with the animation.

table-layout - CSS: Cascading Style Sheets
this can speed up rendering time over the "automatic" layout method, but subsequent cell content might not fit in the column widths provided.

will-change - CSS: Cascading Style Sheets
if your page is performing well, don't add the will-change property to elements just to wring out a little more speed.

Audio and Video Delivery - Developer guides
html5 playbackrate explained the playbackrate property allows us to change the speed or rate at which a piece of web audio or video is playing.

Media events - Developer guides
ratechange sent when the playback speed changes.

HTML5 - Developer guides
performance and integration: providing greater speed optimization and better usage of computer hardware.

Index - Developer guides
14 web audio playbackrate explained apps, audio, media, video, playbackrate the playbackrate property of the <audio> and <video> elements allows us to change the speed, or rate, at which a piece of web audio or video is playing 15 writing web audio api code that works in every browser api you probably have already read the announcement on the web audio api coming to firefox, and are totally excited and ready to make your until-now-webkit-only sites work with firefox, which uses the unprefixed version of the spec.

Separate sites for mobile and desktop - Developer guides
in a nutshell, this technique uses server-side logic to solve all three goals of mobile web development at once — if the user’s browser looks like it’s on a phone, you serve them mobile content, formatted for their phone and optimized for speed.

Optimization and performance - Developer guides
google pagespeed insights lighthouse webpagetest browser developer tools the above resources also include web performance best practices.

<ol>: The Ordered List element - HTML: Hypertext Markup Language
xamples simple example <ol> <li>fee</li> <li>fi</li> <li>fo</li> <li>fum</li> </ol> the above html will output: using roman numeral type <ol type="i"> <li>introduction</li> <li>list of greivances</li> <li>conclusion</li> </ol> the above html will output: using the start attribute <p>finishing places of contestants not in the winners’ circle:</p> <ol start="4"> <li>speedwalk stu</li> <li>saunterin’ sam</li> <li>slowpoke rodriguez</li> </ol> the above html will output: nesting lists <ol> <li>first item</li> <li>second item <!-- closing </li> tag not here!

<picture>: The Picture element - HTML: Hypertext Markup Language
saving bandwidth and speeding page load times by loading the most appropriate image for the viewer's display.

<var>: The Variable element - HTML: Hypertext Markup Language
css var { font: bold 15px "courier", "courier new", monospace; } html <p>the variables <var>minspeed</var> and <var>maxspeed</var> control the minimum and maximum speed of the apparatus in revolutions per minute (rpm).</p> this html uses <var> to enclose the names of two variables.

Preloading content with rel="preload" - HTML: Hypertext Markup Language
<link rel="prerender"> renders a specified webpage in the background, speeding up its load if the user navigates to it.

HTTP conditional requests - HTTP
which client's changes are to be kept, will vary with the speed they commit; this depends on the performance of the clients, of the server, and even of the human editing the document at the client.

Save-Data - HTTP
this could be for reasons such as high transfer costs, slow connection speeds, etc.

HTTP Index - HTTP
this could be for reasons such as high transfer costs, slow connection speeds, etc.

Protocol upgrade mechanism - HTTP
for example: sec-websocket-extensions: superspeed, colormode; depth=16 sec-websocket-key provides information to the server which is needed in order to confirm that the client is entitled to request an upgrade to websocket.

Proxy servers and tunneling - HTTP
reverse proxies have several use cases, a few are: load balancing: distribute the load to several web servers, cache static content: offload the web servers by caching static content like pictures, compression: compress and optimize content to speed up load time.

408 Request Timeout - HTTP
this response is used much more since some browsers, like chrome, firefox 27+, and ie9, use http pre-connection mechanisms to speed up surfing.

HTTP response status codes - HTTP
this response is used much more since some browsers, like chrome, firefox 27+, or ie9, use http pre-connection mechanisms to speed up surfing.

Closures - JavaScript
t be over 16)'} ]; helptext.foreach(function(text) { document.getelementbyid(text.id).onfocus = function() { showhelp(text.help); } }); } setuphelp(); performance considerations it is unwise to unnecessarily create functions within other functions if closures are not needed for a particular task, as it will negatively affect script performance both in terms of processing speed and memory consumption.

Logical nullish assignment (??=) - JavaScript
y; examples using logical nullish assignment function config(options) { options.duration ??= 100; options.speed ??= 25; return options; } config({ duration: 125 }); // { duration: 125, speed: 25 } config({}); // { duration: 100, speed: 25 } specifications specification logical assignment operatorsthe definition of 'assignment operators' in that specification.

Critical rendering path - Web Performance
optimizing for crp improve page load speed by prioritizing which resources get loaded, controlling the order in which they are loaded, and reducing the file sizes of those resources.

Recommended Web Performance Timings: How long is too long? - Web Performance
a 'hello world' on the corporate network would be expected to load in milliseconds, but a user downloading a cat video on a five-year-old device over an edge network in northern siberia would likely find a 20-second download speedy.

Web Performance
y first interactive first meaningful paint first paint http http/2 jank latency lazy load long task lossless compression lossy compression main thread minification network throttling packet page load time page prediction parse perceived performance prefetch prerender quic rail real user monitoring resource timing round trip time (rtt) server timing speculative parsing speed index ssl synthetic monitoring tcp handshake tcp slow start time to first byte time to interactive tls transmission control protocol (tcp) tree shaking web performance documents yet to be written javascript performance best practices javascript, when used properly, can allow for interactive and immersive web experiences ...

The building blocks of responsive design - Progressive web apps (PWAs)
some available solutions are as follows: hisrc a jquery plugin that allows you to create small, medium, and large versions of an image, and then serves the appropriate one according to the browser's resolution and available network speed.

format - SVG: Scalable Vector Graphics
can be used as values for this attribute: format string format truedoc-pfr truedoc™ portable font resource embedded-opentype embedded opentype type-1 postscript™ type 1 truetype truetype opentype opentype, including truetype open truetype-gx truetype with gx extensions speedo speedo intellifont intellifont specifications specification status comment scalable vector graphics (svg) 1.1 (second edition)the definition of 'format for <glyphref>' in that specification.

SVG Attribute reference - SVG: Scalable Vector Graphics
patterntransform patternunits ping pointer-events points pointsatx pointsaty pointsatz preservealpha preserveaspectratio primitiveunits r r radius referrerpolicy refx refy rel rendering-intent repeatcount repeatdur requiredextensions requiredfeatures restart result rotate rx ry s scale seed shape-rendering slope spacing specularconstant specularexponent speed spreadmethod startoffset stddeviation stemh stemv stitchtiles stop-color stop-opacity strikethrough-position strikethrough-thickness string stroke stroke-dasharray stroke-dashoffset stroke-linecap stroke-linejoin stroke-miterlimit stroke-opacity stroke-width style surfacescale systemlanguage t tabindex tablevalues target targetx targety text-anchor text-decoration...

SVG documentation index - SVG: Scalable Vector Graphics
107 image-rendering needsexample, svg, svg attribute the image-rendering attribute provides a hint to the browser about how to make speed vs.

Caching compiled WebAssembly modules - WebAssembly
setting up a caching library because indexeddb is a somewhat old-fashioned api, we wanted to provide a library function to speed up writing caching code, and make it work better along with today's more modern apis.

WebAssembly
in a nutshell webassembly has huge implications for the web platform — it provides a way to run code written in multiple languages on the web at near native speed, with client apps running on the web that previously couldn’t have done so.