RE: [linus:master] [iov_iter] c9eec08bac: vm-scalability.throughput -16.9% regression

David Laight
2023-11-16T16:58:45Z

...
> 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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