qemu-devel
[Top][All Lists]
Advanced
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Qemu-devel] [v2 0/2] add avx2 instruction optimization

From: Eric Blake
Subject: Re: [Qemu-devel] [v2 0/2] add avx2 instruction optimization
Date: Mon, 9 Nov 2015 20:43:00 -0700
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 
On 11/09/2015 07:51 PM, Liang Li wrote:
> buffer_find_nonzero_offset() is a hot function during live migration.
> Now it use SSE2 intructions for optimization. For platform supports
> AVX2 instructions, use the AVX2 instructions for optimization can help
> to improve the performance about 30% comparing to SSE2.

Rather than trying to cater to multiple assembly instruction
implementations ourselves, have you tried taking the ideas in this
earlier thread?
https://lists.gnu.org/archive/html/qemu-devel/2015-10/msg05298.html

Ideally, libc's memcmp() will already be using the most efficient
assembly instructions without us having to reproduce the work of picking
the instructions that work best.

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org

Attachment: signature.asc
Description: OpenPGP digital signature

reply via email to
[Prev in Thread] Current Thread [Next in Thread]