nproc in docs to getconf _NPROCESSORS_ONLN
#30619
Split out of https://github.com/hebasto/bitcoin/pull/316/files#r1711537463
nproc is linux only, getconf _NPROCESSORS_ONLN is used in the Linux kernel for the same task (works on Mac as well): https://github.com/torvalds/linux/blob/master/tools/testing/selftests/rcutorture/bin/kvm-build.sh#L44
On linux:
0# nproc
18
2root@rescue ~ # getconf _NPROCESSORS_ONLN
38
Note that in the productivity doc the recommended core count is one less than before, seems simpler to me this way.
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70+make -j$(getconf _NPROCESSORS_ONLN)
71+```
72+
73+Or is you're on Linux you can even do:
74+```sh
75+make -j$(nproc)
Typo “Or is” -> “Or if”, also missing empty line before next block. My suggestion:
0Linux has the less verbose:
1
2```sh
3make -j$(nproc)
Done, thanks!
These files are also edited during the CMake migration, we can finalize the details once that’s merged.
Reviewed 6d7bf8ea8c11d95ae1cd5b803c151d07cdc2f8d6
Long-time devs state how MacOS is not a supported development platform, and this change does make things more verbose, so I’m curious to get their take. But I’m happy to see there is a way that works for both.
Verified that it does seem to be the right identifier to query by reading: https://www.gnu.org/software/libc/manual/html_node/Processor-Resources.html
You are not changing doc/fuzzing.md which was linked in #30619#issue-2458230769?
nproc is linux only, getconf _NPROCESSORS_ONLN is used in the Linux kernel for the same task: https://github.com/torvalds/linux/blob/master/tools/testing/selftests/rcutorture/bin/kvm-build.sh#L44
Co-authored-by: Hodlinator <172445034+hodlinator@users.noreply.github.com>
nprocis linux only
I don’t think this is true. I don’t have a mac, but I fail to see why installing it won’t work. Also, a bash alias similar to alias nproc="sysctl -n hw.logicalcpu" or alias nproc="getconf _NPROCESSORS_ONLN" should work as well.
No objection to changing this, but I think the claim that nproc is linux-only may not be true.
🐙 This pull request conflicts with the target branch and needs rebase.
getconf _NPROCESSORS_ONLN works on macos out of the box, while nproc isn’t installed by default, but the identifier is so ugly and hard to type i find it an questionable improvement documentation-wise
i find it an questionable improvement documentation-wise
Yeah, would require more thorough doc updates to clarify that - agree, not worth it
Just for reference, the change would be wrong anyway, because the two are used to return different values
0$ podman run --cpuset-cpus=0-1 --rm ubuntu:noble nproc
12
2$ podman run --cpuset-cpus=0-1 --rm ubuntu:noble getconf _NPROCESSORS_ONLN
316
coreutils adds nproc support, so pushed a PR adding that in the OSx docs: https://github.com/bitcoin/bitcoin/pull/30936/files