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Re: [PATCH] x86: Use AVX2 memcpy/memset on Skylake server [BZ #21396]
- From: Florian Weimer <fweimer at redhat dot com>
- To: "H.J. Lu" <hjl dot tools at gmail dot com>
- Cc: libc-alpha at sourceware dot org
- Date: Tue, 18 Apr 2017 21:08:41 +0200
- Subject: Re: [PATCH] x86: Use AVX2 memcpy/memset on Skylake server [BZ #21396]
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On 04/18/2017 08:37 PM, H.J. Lu wrote:
On Skylake server, AVX512 load/store instructions in memcpy/memset may
lead to lower CPU turbo frequency in certain situations. Use of AVX2
in memcpy/memset has been observed to have improved overall performance
in many workloads due to the higher frequency.
Since you bring this up: I think I have read reports that this happens
with AVX2 and some parts, too.
The change itself looks reasonable.
Thanks,
Florian