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Re: [PATCH v2] rwlock: Fix explicit hand-over.
- From: Torvald Riegel <triegel at redhat dot com>
- To: Waiman Long <longman at redhat dot com>
- Cc: Florian Weimer <fw at deneb dot enyo dot de>, GLIBC Devel <libc-alpha at sourceware dot org>, Carlos O'Donell <codonell at redhat dot com>
- Date: Thu, 06 Apr 2017 12:46:53 +0200
- Subject: Re: [PATCH v2] rwlock: Fix explicit hand-over.
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On Mon, 2017-03-27 at 14:59 -0400, Waiman Long wrote:
> Just found out that there is a regression in performance when in writer
> preferring mode. The average per-thread throughput was 4,733 ops/s with
> the old glibc, but 2,300 ops/s with the new implementation vs 32,584
> ops/s for the reader-preferring mode.
Thanks for the note. How large is the performance difference for
different numbers of threads? Is the old rwlock always faster in
writer-preferring mode?