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 Forum: MacBook Pro

Popular Stories

iphone se 4 modified flag edges

iPhone SE 4 With Face ID Said to Be Priced Below $500

Monday May 20, 2024 3:43 am PDT by
Apple is targeting a sub-$500 starting price for its upcoming fourth-generation iPhone SE model despite a raft of rumored upgrades coming to the more affordable device. According to leaker Revegnus on X, the U.S. launch price of the fourth-generation iPhone SE will either remain at the same $429 starting price as the current model, or will see an increase of around 10%. Either way, Apple's...
iOS 17

Apple Releases iOS 17.5.1 With Fix for Reappearing Photos Bug

Monday May 20, 2024 10:11 am PDT by
Apple today released iOS 17.5.1 and iPadOS 17.5.1, minor updates to the iOS 17 and iPadOS 17 operating system updates that came out last September. The 17.5.1 updates come a week after the launch of iOS 17.5 and iPadOS 17.5. iOS 17.5.1 and iPadOS 17.5.1 can be downloaded on eligible iPhones and iPads over-the-air by going to Settings > General > Software Update. According to Apple's...
iPhone 16 Camera Lozenge 2 Perspective

iPhone 16 Lineup Rumored to Come in These Two New Colors

Sunday May 19, 2024 11:08 am PDT by
Apple analyst Ming-Chi Kuo today outlined his expectations for the iPhone 16 lineup's color options, revealing that two new colors should replace two of the existing shades. Kuo outlined his expectations in a post on X (formerly Twitter) earlier today. He believes that the iPhone 16 Pro and iPhone 16 Pro Max will be available in black, white or silver, gray or "Natural Titanium," and rose....
microsoft surface pro qualcomm

Microsoft Says New Surface Pro is Faster Than 15" M3 MacBook Air

Monday May 20, 2024 3:19 pm PDT by
Microsoft is going all in on AI, today introducing a series of Copilot+ PCs that have AI-focused hardware. The new Surface Pro is one of the first Copilot+ PCs, equipped with Qualcomm's Arm-based Snapdragon X Elite processor. Microsoft is already pitting the Surface Pro against Apple's M3 MacBook Air, and in marketing materials, claims that the Surface Pro has superior processing power and...
iOS 17

iOS 17.5 Bug May Also Resurface Deleted Photos on Wiped, Sold Devices [Updated]

Friday May 17, 2024 12:24 pm PDT by
A bug in iOS 17.5 is apparently causing photos that have been deleted to reappear, and the issue seems to impact even iPhones and iPads that have been erased and sold off to other people. A Reddit user wiped an iPad following Apple's guidelines in September of 2023 before selling it off to a friend. That friend updated the iPad to iPadOS 17.5 this week, and began seeing the Reddit user's old ...
iphone se 4 modified flag edges

When to Expect the Next iPhone SE to Launch

Friday May 17, 2024 2:03 pm PDT by
It has been over two years since Apple released the third-generation iPhone SE, and rumors continue to surface about a new model. The latest word comes from The Information, which today reported that Apple plans to release a new iPhone SE with a design similar to the standard iPhone 14 in the spring of 2025. If this rumor is accurate, the iPhone SE would finally gain Face ID and a notch...

Top Rated Comments

Justin941 Avatar
150 months ago
Blur out the names or someone's getting pizzas sent to thier house
Score: 9 Votes (Like | Disagree)
nuckinfutz Avatar
150 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
150 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)
CausticPuppy Avatar
150 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
150 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
150 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)