Getting the cache line size from Zig

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Is there currently a mechanism in the standard library to get the cache line size?

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On linux you can use the sysfs. The size is in /sys/devices/system/node/node*/cpu*/cache/index*/size.
On x86 you can run the CPUID instruction.
I am not aware of anything in the zig library that gets the size. The most relevant is std.posix.linux.PERF.COUNT.HW that can measure cache misses.

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Gotcha, thanks. Is the cache line size runtime-known only / can the same CPU model have different cache line sizes? I’m asking for alignment purposes, if that matters.

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Yes there CPU models may have submodels with different cache sizes.

There is also the syconf API.
Run getconf -a, the parameters are LEVEL?_[ID]CACHE_SIZE

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Okay, thanks.

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Solution: guess cache line size, my guess is 64.

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