Apple Looking to Boost Safari JavaScript Performance with New Accelerator Upgrades

webkit_logoApple is apparently working on significant improvements to JavaScript performance for its Safari browser, as shown by the inclusion of accelerator upgrades in recent builds of WebKit, reports InfoWorld.

WebKit is the open source browser engine created by Apple and which serves as the basis for Safari, and the new upgrades to WebKit's "Nitro" JavaScript engine are known as "FTLJIT". With the upgrades, WebKit's JavaScript engine would become more competitive with Google's V8 and Mozilla's SpiderMonkey engines.

FTLJIT is still considered experimental, so although it's being made available in the OS X port of WebKit by default, it's not actually turned on yet -- it has to be enabled through command-line flags.

One attribute that could make FTLJIT stand out from the pack all the more is how well it runs JavaScript code that is not specifically optimized for [Mozilla's] asm.js. Every JavaScript engine will run asm.js code, but only Mozilla's SpiderMonkey honors asm.js-specific optimizations, and right now no other browser maker has elected to follow Mozilla's lead.

The report notes that speed tests are showing WebKit with FTLJIT enabled outperforming Chrome, while Firefox still tops the charts when using asm.js-optimized benchmark tests.

JavaScript has been a key technology for web browsers for many years, facilitating a variety of user interactions with web pages such as dynamic loading of content without reloading pages and handling page animations and other media. Because JavaScript code embedded on a website is run inside the user's browser when the page is loaded, the efficiency of the browser's JavaScript engine can have a significant impact on the user experience as JavaScript implementations become increasingly complex.

It is unclear whether Apple is targeting OS X 10.10 for these JavaScript improvements, but with them only being enabled in the OS X version of WebKit, it appears that there is still substantial work to be done.

Popular Stories

iPhone 17 Pro Dark Blue and Orange

iPhone 17 Release Date, Pre-Orders, and What to Expect

Thursday August 28, 2025 4:08 am PDT by
An iPhone 17 announcement is a dead cert for September 2025 – Apple has already sent out invites for an "Awe dropping" event on Tuesday, September 9 at the Apple Park campus in Cupertino, California. The timing follows Apple's trend of introducing new iPhone models annually in the fall. At the event, Apple is expected to unveil its new-generation iPhone 17, an all-new ultra-thin iPhone 17...
iPhone 17 Pro Iridescent Feature 2

iPhone 17 Pro Clear Case Leak Reveals Three Key Changes

Sunday August 31, 2025 1:26 pm PDT by
Apple is expected to unveil the iPhone 17 series on Tuesday, September 9, and last-minute rumors about the devices continue to surface. The latest info comes from a leaker known as Majin Bu, who has shared alleged images of Apple's Clear Case for the iPhone 17 Pro and Pro Max, or at least replicas. Image Credit: @MajinBuOfficial The images show three alleged changes compared to Apple's iP...
xiaomi apple ad india

Apple and Samsung Push Back Against Xiaomi's Bold India Ads

Friday August 29, 2025 4:54 am PDT by
Apple and Samsung have reportedly issued cease-and-desist notices to Xiaomi in India for an ad campaign that directly compares the rivals' devices to Xiaomi's products. The two companies have threatened the Chinese vendor with legal action, calling the ads "disparaging." Ads have appeared in local print media and on social media that take pot shots at the competitors' premium offerings. One...
iphone 16 pro ghost hand

iPhone 17 Pro: 5 Reasons Not to Upgrade This Year

Monday September 1, 2025 4:35 am PDT by
Apple will launch its new iPhone 17 series this month, and the iPhone 17 Pro models are expected to get a new design for the rear casing and the camera area. But more significant changes to the lineup are not expected until next year, when the iPhone 18 models arrive. If you're thinking of trading in your iPhone for this year's latest, consider the following features rumored to be coming to...
iOS 18 on iPhone Arrow Down

Apple Preparing iOS 18.7 for iPhones as iOS 26 Release Date Nears

Sunday August 31, 2025 4:35 pm PDT by
Apple is preparing to release iOS 18.7 for compatible iPhone models, according to evidence of the update in the MacRumors visitor logs. We expect iOS 18.7 to be released in September, alongside iOS 26. The update will likely include fixes for security vulnerabilities, but little else. iOS 18.7 will be one of the final updates ever released for the iPhone XS, iPhone XS Max, and iPhone XR,...

Top Rated Comments

JoshDoug Avatar
148 months ago
Expecting some witty and original comments on this thread.
Score: 32 Votes (Like | Disagree)
troop231 Avatar
148 months ago
Yay! News about a snappier safari and not beats!!!

Oh no, I didn't :p

MacRumors content image
Score: 30 Votes (Like | Disagree)
thekeyring Avatar
148 months ago
I wonder if anyone will comment "isn't OS X 10.10 the same as 10.1?" :rolleyes:
Score: 25 Votes (Like | Disagree)
mohdamerul Avatar
148 months ago
can't get snappier anymore my ass :p
Score: 17 Votes (Like | Disagree)
jmh600cbr Avatar
148 months ago
Yay! News about a snappier safari and not beats!!!
Score: 17 Votes (Like | Disagree)
iLoveiTunes Avatar
148 months ago
snappier safari..ah, good times
Score: 15 Votes (Like | Disagree)