Messages in this thread | | | From | David Laight <> | Subject | RE: [linus:master] [iov_iter] c9eec08bac: vm-scalability.throughput -16.9% regression | Date | Thu, 16 Nov 2023 16:58:44 +0000 |
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... > Of course, it's also possible that with all the function call overhead > introduced by the CPU mitigations on older CPU's, we should just say > "rep movsb" is always correct - if you have a new CPU with FSRM it's > good, and if you have an old CPU it's no worse than the horrendous CPU > mitigation overhead for function call/returns.
Unless you are stupid enough to use a P4 :-)
I actually doubt anyone cares (esp. for 64bit) about any cpu that don't optimise long 'rep movsb' (pre sandy bridge).
David
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