Comments on: Followup To The Myth Of Cocoa Apps http://www.symphonious.net/2007/08/29/followup-to-the-myth-of-cocoa-apps/ Living in a state of accord. Wed, 03 Dec 2008 20:09:12 +0000 http://wordpress.org/?v=2.6.5 By: Adrian Sutton http://www.symphonious.net/2007/08/29/followup-to-the-myth-of-cocoa-apps/#comment-107391 Adrian Sutton Wed, 29 Aug 2007 07:52:30 +0000 https://www.symphonious.net/2007/08/29/followup-to-the-myth-of-cocoa-apps/#comment-107391 Ben, Good to hear someone doing some actual profiling, but what actually matters here isn't the underlying calls - it's Parallels itself. If 99% of the time Parallels is handling memory translation for the guest OS, nothing you do in the GUI will impact performance. You need to look at the overall picture to get the real answer. That said, this is the closest to actual data we've seen so far so thank you. I would ask though, how did you determine which OpenGL calls Parallels is using? Would it be possible for their code to have specifically optimized sections such that they make better use of OpenGL or otherwise change the performance? Ben,
Good to hear someone doing some actual profiling, but what actually matters here isn’t the underlying calls - it’s Parallels itself. If 99% of the time Parallels is handling memory translation for the guest OS, nothing you do in the GUI will impact performance. You need to look at the overall picture to get the real answer.

That said, this is the closest to actual data we’ve seen so far so thank you. I would ask though, how did you determine which OpenGL calls Parallels is using? Would it be possible for their code to have specifically optimized sections such that they make better use of OpenGL or otherwise change the performance?

]]> By: Ben G. http://www.symphonious.net/2007/08/29/followup-to-the-myth-of-cocoa-apps/#comment-107390 Ben G. Wed, 29 Aug 2007 07:10:34 +0000 https://www.symphonious.net/2007/08/29/followup-to-the-myth-of-cocoa-apps/#comment-107390 Hi Adrian, I've personally profiled the OpenGL calls that Parallels' Qt functions end up using to render the SVGA framebuffer of a virtual machine, and they're slower than the native OpenGL calls VMware Fusion uses. In addition, take a look at the WindowServer process before and after starting Parallels and booting a virtual machine. You'll see it's a pretty hefty drain; Qt creates literally hundreds of hidden windows whenever you use it on Mac OS (this is not a Parallels issue; it's a Qt issue) and it causes the Quartz window server to gobble up memory like crazy. Now, this isn't to say that Qt can't be as fast as OpenGL and Cocoa. It can. But, like any multiplatform toolkit, that's not its forte; it's good at making UIs quickly portable to dozens of platforms with a semi-native UI, which is why Parallels uses it. Hi Adrian,

I’ve personally profiled the OpenGL calls that Parallels’ Qt functions end up using to render the SVGA framebuffer of a virtual machine, and they’re slower than the native OpenGL calls VMware Fusion uses.

In addition, take a look at the WindowServer process before and after starting Parallels and booting a virtual machine. You’ll see it’s a pretty hefty drain; Qt creates literally hundreds of hidden windows whenever you use it on Mac OS (this is not a Parallels issue; it’s a Qt issue) and it causes the Quartz window server to gobble up memory like crazy.

Now, this isn’t to say that Qt can’t be as fast as OpenGL and Cocoa. It can. But, like any multiplatform toolkit, that’s not its forte; it’s good at making UIs quickly portable to dozens of platforms with a semi-native UI, which is why Parallels uses it.

]]> By: Adrian Sutton http://www.symphonious.net/2007/08/29/followup-to-the-myth-of-cocoa-apps/#comment-107347 Adrian Sutton Wed, 29 Aug 2007 01:18:07 +0000 https://www.symphonious.net/2007/08/29/followup-to-the-myth-of-cocoa-apps/#comment-107347 Whether or not Fusion is faster than Parallels doesn't affect what they know about *why* Parallels performs the way it does. The Fusion team seemed to care enough to pay attention to that thread on my blog as did thousands of other people, so it would seem important enough for people to comment on. I'd also appreciate it if we could steer away from insults and stick to civil discussion. Whether or not Fusion is faster than Parallels doesn’t affect what they know about *why* Parallels performs the way it does. The Fusion team seemed to care enough to pay attention to that thread on my blog as did thousands of other people, so it would seem important enough for people to comment on.

I’d also appreciate it if we could steer away from insults and stick to civil discussion.

]]> By: Pierre Lefranc http://www.symphonious.net/2007/08/29/followup-to-the-myth-of-cocoa-apps/#comment-107346 Pierre Lefranc Wed, 29 Aug 2007 01:03:40 +0000 https://www.symphonious.net/2007/08/29/followup-to-the-myth-of-cocoa-apps/#comment-107346 > My interpretation is that VMWare are just guessing at the performance characteristics of their competitor Given how Fusion trounces Parallels in benchmarks (http://www.macnn.com/articles/07/08/16/fusion.vs.parallels/), I don't think VMWare is just guessing... > Parallels really need to learn about blog search engines and stay on top of these conversations. Do you think that thread on your blog was that interesting that the world should stop and comment on it? By continuing to talk about this insignificant issue, you certainly seem like somebody with too much time in his hands. > My interpretation is that VMWare are just guessing at the performance characteristics of their competitor

Given how Fusion trounces Parallels in benchmarks (http://www.macnn.com/articles/07/08/16/fusion.vs.parallels/), I don’t think VMWare is just guessing…

> Parallels really need to learn about blog search engines and stay on top of these conversations.

Do you think that thread on your blog was that interesting that the world should stop and comment on it? By continuing to talk about this insignificant issue, you certainly seem like somebody with too much time in his hands.

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