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From:   David Howells <dhowells@redhat.com>
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To:     David Laight <David.Laight@ACULAB.COM>
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Subject: Re: [linus:master] [iov_iter] c9eec08bac: vm-scalability.throughput -16.9% regression
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Date:   Thu, 16 Nov 2023 10:14:03 +0000
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David Laight <David.Laight@ACULAB.COM> wrote:

> On haswell (which is now quite old) both 'rep movsb' and
> 'rep movsq' copy 16 bytes/clock unless the destination
> is 32 byte aligned when they copy 32 bytes/clock.
> Source alignment make no different, neither does byte
> alignment.

I think the i3-4170 cpu I'm using is Haswell.  Does that mean for my
particular cpu, just using inline "rep movsb" is the best choice?

David