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A comment on Mkfile(8) is severely syscall limited on OS X. Parent comment

Re:Mkfile(8) is severely syscall limited on OS X by geocar on Sunday February 12, 2017 @10:37AM (#13628804)
I don't think anyone seriously expects OSX to be as performant as Linux, since it doesn't feel faster, and a lot of the problems are obviously[1] the results of the microkernel side. That being said, a little googling shows a direct head-to-head[2] comparison.

[1]: http://sekhon.berkeley.edu/macosx/

[2]: http://www.academia.edu/2685902/An_Analysis_of_Mac_OS_X_Leop...

I have spent a great deal of time studying the code path taken on system calls in xnu/osfmk[3] versus Linux[4] in building my Linux emulator for OSX[5].

[3]: https://opensource.apple.com/source/xnu/xnu-1504.3.12/osfmk/...

[4]: https://github.com/torvalds/linux/blob/master/arch/x86/entry...

[5]: https://github.com/geocar/ml/

I think many OSX supporters do the platform a disservice by defending it without spending any time studying it or the competition. OSX has some serious performance-based weaknesses, that are perhaps a real worthwhile trade for a lot of things "just working" -- especially when compared to Windows or Linux -- but are still a weakness.

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Re:Mkfile(8) is severely syscall limited on OS X by bogomipz on Sunday February 12, 2017 @11:12AM (#13628969)
I certainly wouldn't classify myself as an "OS X" supporter by any means. I don't think I've ever actually defended it :)

I was more responding to the blanket statement that system calls are more expensive on OS X.

You first citation is ancient by the way, thats 11 years ago now.

You second link states in the conclusion section:

"First, Mac OSX uses a hybrid monolithic and microkernel architecture inwhich system calls must be wrapped into an RPC messageto the Mach microkernel. "

But in XNU/Darwin there are three different mechanism for systems calls - traditional BSD style traps, Mach traps, and Mach RPC.

I didn't really understand how the other 3 links related or I guess specifically what I was looking for in those.

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