Latest WebKit Builds Address Browser Scrolling Performance on Retina MacBook Pro Models - MacRumorsOpen MenuShow RoundupsShow Forums menuVisit ForumsOpen Sidebar
Skip to Content

Latest WebKit Builds Address Browser Scrolling Performance on Retina MacBook Pro Models

Soon after the launch of the 15-inch Retina MacBook Pro in June, we pointed to an analysis by AnandTech showing how the need to drive a massive number of pixels taxed the graphics capabilities of the machine to the point where it struggled to hit 20 frames per second while scrolling on resource-intensive web pages such as Facebook news feeds.

AnandTech now follows up with a new report based on a thread in our forums showing that the latest builds of WebKit, the open source browser engine upon which Safari is based, demonstrate dramatically improved frame rates during scrolling.

I grabbed a build (r135516 - it's no longer the latest build but I assume the later builds also contain the fix) and tried it out on the 13-inch rMBP. Scrolling down my Facebook news feed ended up being one of the best showcases for poor scrolling performance on the rMBPs, so that's obviously the first test I ran. As always I used Quartz Debug to measure UI frame rate.

The results show frame rates of around 20 frames per second (fps) under the standard Safari 6.0.2, but jump to nearly 50 fps when using nightly build r135516 of WebKit.

webkit retina frame rate
Frame rates approaching 50 fps when scrolling in WebKit nightly build r135515

AnandTech hasn't been able to determine exactly what code changes were made to enable the significant boost to scrolling performance on Retina MacBook Pro models, and it is unclear exactly when those changes will be incorporated into Safari itself, but it certainly seems that a solution is on its way.

Related Roundup: MacBook Pro

Popular Stories

duo aquarium

More Fun iPhone Duo Apps: 30 New Picks to Try

Friday November 6, 2026 3:27 pm PST by
When the iPhone Duo launched, we shared a list of some of the fun apps developers created for the new form factor. Two weeks out, developers are continuing to come up with fresh ideas, so we thought we'd share some of our favorites. Games Marbles Unhinged ($2.99) - Marbles Unhinged is a marble maze designed for the Duo. When you fold it, the floor turns into a ramp. If you stand the top...
iOS 28 AI

Apple Taking New Approach to Developing iOS 28 and macOS 28

Sunday November 8, 2026 7:42 am PST by
Apple has made a change to its development process for iOS 28, macOS 28, and corresponding software updates, according to Bloomberg's Mark Gurman. In his Power On newsletter today, he said Apple separates development of each year's new operating systems into three major stages. Typically, he said each stage consists of four weeks of coding followed by a four-week "convergence" period where...
apple pro tell logo

Apple Launching Five New Products Today

Thursday November 5, 2026 12:59 am PST by
Apple is launching five new products on Friday, November 6, following pre-orders that opened last week, including its first touchscreen MacBook Pro models. The following new products will be available from today: iPad mini with OLED display and A20 Pro chip iMac with M6 chip 14-inch MacBook Pro with M6 chip 14-inch MacBook Pro with OLED touchscreen 16-inch MacBook Pro with OLED...

Top Rated Comments

182 months ago
Blur out the names or someone's getting pizzas sent to thier house
Score: 9 Votes (Like | Disagree)
nuckinfutz Avatar
182 months ago
So why did Apple release a product that clearly wasn't ready yet?
When is anything every ready in this industry?

Everything is in constant motion.
Score: 7 Votes (Like | Disagree)
nuckinfutz Avatar
182 months ago
Apple didn't do anything, webkit did which is mostly people from KHTML which is what webkit was forked from.

That was ages ago. Today's webkit is a much larger beast than that old KHTML. Go ask Dave Hyatt how much work he's put into Webkit as an Apple employee.

To say Apple hasn't make a significant investment in Webkit is to be either ignorant or foolish or both.
Score: 4 Votes (Like | Disagree)
182 months ago
Sweet.

It's a shame so many "trusted" review sites (including The Verge) dinged the rMBP and blamed the hardware.... for what is clearly a software problem.
Score: 4 Votes (Like | Disagree)
ironsienna Avatar
182 months ago
Great, that was the major concern I had that was holding me from purchase a new macbook pro: Poor web browsing performance. Kudos to Apple, for working on optimising the code rather than trying to sell another model with faster processor in just a few months. I am so glad they managed to address this as it was rather irritating...
Score: 4 Votes (Like | Disagree)
KnightWRX Avatar
182 months ago
That's incorrect and has been pointed out a gazilionth times here. It has everything to do with pixel pushing power, the ACD might have the same resolution with the 13" mbp, in the later the resolution is doubled and then halved (or adjusted to some %) to fit the screen. Thus it's the overhead to run 4 ACDs (no of pixel quadrupled) not one, plus the processing cost of then adjusting it to the actual screen size. When the no of pixels you render are QUADRUPLED you bet it has everything to do with pixel pushing power.
You're saying the same thing I am except making a few wrong assumptions. The resolution isn't doubled then halved at all in HiDPI mode, it's only downscaled after upscaling if you use the scaled modes (1680x1050 or 1920x1200). Running at 1440x900 (2880x1800) only upscales non-Retina graphics to 2880x1800 and leaves it at that. Running 1920x1200 (which I run permenantly) runs a 3840x2400 framebuffer which it then downscales to 2880x1800 for displaying on the display.

And what I've been saying all along is quite correct, the problem is not the pixel pushing ability of the GPU. Pixel fill rates, look them up. Again, if you can't understand that a 4 year old GPU, the 9400m, could power a 30" ACD and that we're now in 2012, 4 years later, with GPUs 3 generations newer, I don't know how to explain it to you.

The 9400m could push 2.32 GP/s. Again, 4 years ago. 2880x1800 at 60 fps is roughly 311 MP/s. Are you getting this ? Even if what you say is true and HiDPI was so horridly optimized as you claim (which it isn't), that's still only half of the pixel fill rate of a now 4 year old Integrated GPU.

Anyway, I own a rMBP 15" and I've hardly met any "lag" whatsoever. I guess some people are just too sensitive. Thank god Apple knows it's a software issue and is fixing it for those people.

----------

It's not a bs argument, it's not powerful enough indeed. The ui still lags and stutters. The current hardware is just not capable enough. It's an air cpu circa rev. 1. Apple have hacked their way to resolution independence with rendering twice the resolution canvas so as to avoid what win 8 did and go into detail about interface elements. They thus offloaded all the complexity on the hardware, and the hardware isn't there yet. Simple as that. Rev. 1 retina macbook pros are a major compromise. I am still planning to go ahead and buy one, fyi, but If I do I ll be do it in fully aware that I am buying a problematic rev. 1 product, not only for the image retention issue with the lg screen, but also for the gfx barely making it there.

The hardware is capable. You just don't understand GPU hardware or HiDPI to make such claims. Anand has always been full of it.
Score: 3 Votes (Like | Disagree)
Latest Stories
Apple Store Subscription Sign-Up Controversy Exposed
Apple Store Subscription Sign-Up Controversy Exposed
9 hours ago
Siri AI Rumored to Become 'More Like an Agent' as Early as Next Year
Siri AI Rumored to Become 'More Like an Agent' as Early as Next Year
19 hours ago
Apple Taking New Approach to Developing iOS 28 and macOS 28
Apple Taking New Approach to Developing iOS 28 and macOS 28
20 hours ago
Early Apple Black Friday Deals on Apple Watch, MacBook Air, and More
Early Apple Black Friday Deals on Apple Watch, MacBook Air, and More
2 days ago
'Backglow' Lets You Customize New MacBook Pro's Glowing Apple Logo
'Backglow' Lets You Customize New MacBook Pro's Glowing Apple Logo
2 days ago
Top Stories: Apple Product Launches, iOS 27.3 Beta, and More
Top Stories: Apple Product Launches, iOS 27.3 Beta, and More
2 days ago
More Fun iPhone Duo Apps: 30 New Picks to Try
More Fun iPhone Duo Apps: 30 New Picks to Try
3 days ago
Hands-On With Apple's New OLED Touchscreen MacBook Pro
Hands-On With Apple's New OLED Touchscreen MacBook Pro
3 days ago
Apple Store With All-New Design Opening Soon in Southern California
Apple Store With All-New Design Opening Soon in Southern California
3 days ago
Control the Glowing Apple Logo on Your New MacBook Pro
Control the Glowing Apple Logo on Your New MacBook Pro
3 days ago
Apple Shares New 'Apple Card: Apply and Use in Minutes' Ad
Apple Shares New 'Apple Card: Apply and Use in Minutes' Ad
3 days ago
Apple Says More Than 100,000 Apps Optimized for iPhone Duo, Here's What's Still Missing
Apple Says More Than 100,000 Apps Optimized for iPhone Duo, Here's What's Still Missing
3 days ago
Early Black Friday Deals Kickoff With Steep Discounts on Apple Watch Ultras and More
Early Black Friday Deals Kickoff With Steep Discounts on Apple Watch Ultras and More
3 days ago
The MacRumors Show: iOS 27.3 Looks Like a Huge Update
The MacRumors Show: iOS 27.3 Looks Like a Huge Update
3 days ago
Best Buy's Black Friday Event Begins With Sitewide Savings on Apple, TVs, More
Best Buy's Black Friday Event Begins With Sitewide Savings on Apple, TVs, More
3 days ago
Apple Releasing Yet Another Two New Products Next Week
Apple Releasing Yet Another Two New Products Next Week
3 days ago
MacBook Air Drops to Lowest Price in Months With Amazon's $250 Discount
MacBook Air Drops to Lowest Price in Months With Amazon's $250 Discount
3 days ago
Apple Rumored to Drop the iPhone's Action Button Next Year
Apple Rumored to Drop the iPhone's Action Button Next Year
3 days ago
Apple's Extended Return Policy Now in Effect for 2026 Holiday Season
Apple's Extended Return Policy Now in Effect for 2026 Holiday Season
3 days ago
Apple Music Classical Updated With New Icon and Refreshed Design
Apple Music Classical Updated With New Icon and Refreshed Design
3 days ago
OLED iPad Mini, M6 iMac, and New MacBook Pros Available From Today
OLED iPad Mini, M6 iMac, and New MacBook Pros Available From Today
3 days ago
Apple Surveys iPhone Duo Buyers About Crease and Camera
Apple Surveys iPhone Duo Buyers About Crease and Camera
4 days ago
Apple's First Touchscreen Mac is Now Arriving to Customers
Apple's First Touchscreen Mac is Now Arriving to Customers
4 days ago
Claude Gets Personal Finance Feature With Bank Account Linking
Claude Gets Personal Finance Feature With Bank Account Linking
4 days ago
Apple Arcade Adds Crossy Road Rush and NBA 2K27
Apple Arcade Adds Crossy Road Rush and NBA 2K27
4 days ago
Apple's New HomeView Smart Home Hub: Here's How Much RAM It Has
Apple's New HomeView Smart Home Hub: Here's How Much RAM It Has
4 days ago
iPad Mini vs. iPad Air Buyer's Guide: Now Just $50 Apart
iPad Mini vs. iPad Air Buyer's Guide: Now Just $50 Apart
4 days ago
First iOS 27.3 and macOS Golden Gate 27.3 Public Betas Now Available
First iOS 27.3 and macOS Golden Gate 27.3 Public Betas Now Available
4 days ago
Apple Announces a New Mac Sales Record
Apple Announces a New Mac Sales Record
4 days ago
Paid $200 for Logic Pro? Apple Says You Won't Get This New Feature
Paid $200 for Logic Pro? Apple Says You Won't Get This New Feature
4 days ago