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Apple Disputes Browser Speed Findings, Says Mobile Safari's the True Contender
An anonymous reader writes "Apple has hit back over claims that the browser shipped with its iPhone, iPod Touch, and iPad devices is significantly slower than Android's equivalent, calling the independent testing 'flawed.' 'They didn't actually test the Safari browser on the iPhone,' Apple's Kerris argues. 'Instead they only tested their own proprietary app, which uses an embedded Web viewer that doesn't actually take advantage of Safari's Web performance optimisations.' This, claims testing firm Blaze.io, is news to the world. 'Embedded browsers are expected to behave, for the most part, the same as the regular browser,' the company stated, defending its methodology. 'However, Apple is now stating that their embedded browser, called UIWebView, does not share the same optimisations MobileSafari does.'"
if "slow" means "the same speed as they were two weeks ago when we weren't complaining about how slow they are", then, yes, they run at the same speed they did two weeks ago when nobody was complaining how slow they were. If you have a 10 terrabyte porn collection, you don't lose porn just because your friend has a 15 terrabyte porn collection.
Do you even lift?
These aren't the 'roids you're looking for.
The problem isn't with the intentional ARM code written by the applications. It is with code injected into the application (via an exploitable bug, like a buffer overflow) by malicious software. Setting noexec on data pages and nowrite on code pages is a security feature that prevents a large class of remote exploits, by ensuring that only the original code is executed.
Compiling code on the fly should only be allowed on applications that have been carefully scrutinized for bugs, not every crappy app with an embedded web-browser. Even enabling it for Safari is risky, but is a lower attack surface than enabling it for any and all apps.
Once iOS gains WebKit 2, this issue should go away. Development activity is pretty rapid right now, so there may be a big push to have this done for iOS 5. A story on Ars indicates bugs about web apps not using the new Nitro engine were closed with "not to be fixed by exec order". Based on that, I'm guessing the following occurred:
Apple execs wanted web browsing to be faster on iOS, by taking advantage of the same tech that is being used to accelerate browsers on the desktop. They also wanted to maintain the secure environment in iOS, and bring more security to the OS X side. WebKit 2 had been in development internally for a little while, and was opened up to the public for contributions in April 2010. Google, and others have been making major contributions to it, and development is proceeding.
Apple also had plans to release the iPad 2, along with an eventual iPhone 5 and new iPod Touch featuring dual core processors. iOS 5 is too far out, so iOS 4.3 had a lot of development effort spent on making MobileSafari faster. Because WebKit 2 wasn't ready, security wasn't ready to open it up to the world, and the decision was made to do what they could in the time frame allowed, and make it open to other developers later.
The "not to be fixed by exec order" is likely in place to prevent engineers from wasting time on trying to bring new improvements to old frameworks, and instead keeping engineers focused on finishing iOS 5, possibly with WebKit 2 in time for the iPhone 5 release this summer.
Apple is a hardware company (as far as where the majority of their profits come from), and so software development relating to iOS will always be driven by hardware release cycles. They may slip features from software, but key pieces have to be in place to meet the hardware cycle. It's looking like March will be new iPad time, June for iPhones, then September for iPods. iPads will debut new CPUs, iPhones will debut new major iOS releases and some other features (gyroscope, possibly NFC, etc), and iPods will just be a phoneless iPhone. Each release comes with a new iOS, iPad being a final point release of the previous iOS, iPhone being the new one, then iPods gaining the first point release of the new OS.
The problem is not using ARM instructions. The problem is where those ARM instructions are. The iPhone presumably uses something like the NX bit to segregate data from code. Because of the way a JIT works, it needs to be able to execute code in the data area of memory. Allowing every app to do this would effectively eliminate the additional security that the NX bit provides.
No. Google's JIT is just as insecure. The problem is not in the implementation, it's that you need to disable the NX bit on an area of memory to run a JIT at all. There is no workaround to this, unless the JIT isn't actually a just in time compiler.
You don't have to be Nostradamus to see what debate that "reasons unknown" part is going to cause.
Yeah but if you were Nostradamus, the predictions would be much more fun.
Quatrain XI: The searching metal man roze to fell the mighty apple. Chrome, Fire, and Foxes all rejoiced at the silence atop the buffering hills.
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