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From:   David Howells <dhowells@redhat.com>
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References: <168979148257.1905271.8311839188162164611.stgit@morisot.1015granger.net> <168979108540.1905271.9720708849149797793.stgit@morisot.1015granger.net>
To:     Chuck Lever <cel@kernel.org>
Cc:     dhowells@redhat.com, linux-nfs@vger.kernel.org,
        netdev@vger.kernel.org, Chuck Lever <chuck.lever@oracle.com>
Subject: Re: [PATCH v3 4/5] SUNRPC: Revert e0a912e8ddba
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Date:   Wed, 26 Jul 2023 13:14:31 +0100
Message-ID: <6618.1690373671@warthog.procyon.org.uk>
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Chuck Lever <cel@kernel.org> wrote:

> Flamegraph analysis showed that the cork/uncork calls consume
> nearly a third of the CPU time spent in svc_tcp_sendto(). The
> other two consumers are mutex lock/unlock and svc_tcp_sendmsg().
> 
> Now that svc_tcp_sendto() coalesces RPC messages properly, there
> is no need to introduce artificial delays to prevent sending
> partial messages.
> 
> After applying this change, I measured a 1.2K read IOPS increase
> for 8KB random I/O (several percent) on 56Gb IP over IB.
> 
> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Reviewed-by: David Howells <dhowells@redhat.com>