Global Kernel Locks in APFS
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Global Kernel Locks in APFS
1–10 of 47 posts
Re: Global Kernel Locks in APFS
#2The author worked very hard to determine the root cause of the problem but he was stymied because the APFS source code is not available. Why not? Apple has open-sourced the Swift compiler with great success, but there seems to be no movement within Apple to open up other system software components.
Re: Global Kernel Locks in APFS
#3The author worked very hard to determine the root cause of the problem but he was stymied because the APFS source code is not available. Why not? Apple has open-sourced the Swift compiler with great success, but there seems to be no movement within Apple to open up other system software components.
Apple releases most of the macOS kernel but I guess it doesn't include APFS: https://opensource.apple.com/source/xnu/
Re: Global Kernel Locks in APFS
#4The author worked very hard to determine the root cause of the problem but he was stymied because the APFS source code is not available. Why not? Apple has open-sourced the Swift compiler with great success, but there seems to be no movement within Apple to open up other system software components.
Pretty sure the code would expose just how much of a rush-job apple did with APFS. It may be released one day..
Re: Global Kernel Locks in APFS
#5The author worked very hard to determine the root cause of the problem but he was stymied because the APFS source code is not available. Why not? Apple has open-sourced the Swift compiler with great success, but there seems to be no movement within Apple to open up other system software components.
Apple releases most of the macOS kernel but I guess it doesn't include APFS: https://opensource.apple.com/source/xnu/
That's missing a good chunk of the interesting stuff related to how users interact with the os though. (app and framework source code)
Re: Global Kernel Locks in APFS
#6Earlier quoted context omitted.
Apple releases most of the macOS kernel but I guess it doesn't include APFS: https://opensource.apple.com/source/xnu/
That's missing a good chunk of the interesting stuff related to how users interact with the os though. (app and framework source code)
Yeah, apps and frameworks aren't part of the kernel. But APFS is.
Re: Global Kernel Locks in APFS
#7The author worked very hard to determine the root cause of the problem but he was stymied because the APFS source code is not available. Why not? Apple has open-sourced the Swift compiler with great success, but there seems to be no movement within Apple to open up other system software components.
They do plan to document it fully later:
> Is APFS open source?
> An open source implementation is not available at this time. Apple plans to document and publish the APFS volume format specification.
Source: https://developer.apple.com/library/archive/documentation/Fi...
My theory is that Apple rushed APFS and its implementation isn't in a great shape for the public review. APFS doesn't feel any faster on my SSDs on macOS. I suspect they'll add it in a few years, after a few iterations.
Re: Global Kernel Locks in APFS
#8Earlier quoted context omitted.
That's missing a good chunk of the interesting stuff related to how users interact with the os though. (app and framework source code)
Yeah, apps and frameworks aren't part of the kernel. But APFS is.
Kind of talking out of my ass, but Darwin can act as a mirokernel, so APFS could be implemented as a user mode service (no idea if it's the case, though).
Re: Global Kernel Locks in APFS
#9The author worked very hard to determine the root cause of the problem but he was stymied because the APFS source code is not available. Why not? Apple has open-sourced the Swift compiler with great success, but there seems to be no movement within Apple to open up other system software components.
They do plan to document it fully later: > Is APFS open source? > An open source implementation is not available at this time. Apple plans to document and publish the APFS volume format specification. Source: https://developer.apple.com/library/archive/documentation/Fi... My theory is that Apple rushed APFS and its implementation isn't in a great shape for the public review. APFS doesn't feel any faster on my SSDs on…
They released the format spec here: https://developer.apple.com/support/apple-file-system/Apple-...
Re: Global Kernel Locks in APFS
#10The author worked very hard to determine the root cause of the problem but he was stymied because the APFS source code is not available. Why not? Apple has open-sourced the Swift compiler with great success, but there seems to be no movement within Apple to open up other system software components.
They do plan to document it fully later: > Is APFS open source? > An open source implementation is not available at this time. Apple plans to document and publish the APFS volume format specification. Source: https://developer.apple.com/library/archive/documentation/Fi... My theory is that Apple rushed APFS and its implementation isn't in a great shape for the public review. APFS doesn't feel any faster on my SSDs on…
> They do plan to document it fully later:
> > Is APFS open source?
> > An open source implementation is not available at this time. Apple plans to document and publish the APFS volume format specification.
They claim to plan to document it fully later.