netdev - Re: [PATCH] net/core/sock.c remove extra wakeup

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Date:	Wed, 11 Jun 2008 16:46:12 +1000
From:	Herbert Xu <herbert@...dor.apana.org.au>
To:	GHaskins@...ell.com (Gregory Haskins)
Cc:	davem@...emloft.net, PMullaney@...ell.com, netdev@...r.kernel.org
Subject: Re: [PATCH] net/core/sock.c remove extra wakeup

Gregory Haskins <GHaskins@...ell.com> wrote:
> 
> So basically it was waiting for a packet to arrive, and the net-rx softirq would first trigger a NOSPACE wakeup (of which was a noop by the udp-rx code) followed by an rx-wakeup.  So the netperf thread woke twice for one packet.  Fixing this boosted performance by a large margin (don't recall exact figures off the top of my head....somewhere around 20%)

Please wrap your lines.

Anyway, you've lost me with this scenario.  The patch is stopping
wake-ups on the write path yet you're talking about the read path.
So my question is why are you getting the extra wake-up on that
write path when you receive a packet?

Cheers,
-- 
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Email: Herbert Xu ~{PmV>HI~} <herbert@...dor.apana.org.au>
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