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From: Florian Weimer <fweimer@redhat.com>
To: Shuo Wang <wangshuo47@huawei.com>
Cc: <hjl.tools@gmail.com>, <libc-alpha@sourceware.org>, hushiyuan@huawei.com
Subject: Re: x86-64: memcpy performance reduce when running in virtual mechine
Date: Mon, 11 Jan 2021 10:06:31 +0100	[thread overview]
Message-ID: <87eeirsuzs.fsf@oldenburg2.str.redhat.com> (raw)
In-Reply-To: <20210111083848.22496-1-wangshuo47@huawei.com> (Shuo Wang's message of "Mon, 11 Jan 2021 16:38:48 +0800")

* Shuo Wang:

> The environment information is as follows:
> [host]
> - kernel version: 4.18.0
> - glibc version: 2.28
> - gcc version: 8.3.1
> - qemu version: 2.12.0
> - libvirtd version: 4.5.0

Does your have a glibc a backport of this patch?

commit d3c57027470b78dba79c6d931e4e409b1fecfc80
Author: Patrick McGehearty <patrick.mcgehearty@oracle.com>
Date:   Mon Sep 28 20:11:28 2020 +0000

    Reversing calculation of __x86_shared_non_temporal_threshold

Some hypervisors set the number of reported threads in CPUID to zero.

Thanks,
Florian
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  reply	other threads:[~2021-01-11  9:06 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-01-11  8:38 Shuo Wang
2021-01-11  9:06 ` Florian Weimer [this message]
2021-01-11  8:41 Shuo Wang
2021-01-11 14:32 Shuo Wang
2021-01-11 15:09 ` Florian Weimer

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