Re: regression with poll(2)

From: Eric Dumazet
Date: Mon Aug 20 2012 - 05:33:20 EST


On Mon, 2012-08-20 at 10:04 +0100, Mel Gorman wrote:

> Can the following patch be tested please? It is reported to fix an fio
> regression that may be similar to what you are experiencing but has not
> been picked up yet.
>
> -

This seems to help here.

Boot your machine with "mem=768M" or a bit less depending on your setup,
and try a netperf.

-> before patch :

# netperf
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to
localhost.localdomain () port 0 AF_INET
Recv Send Send
Socket Socket Message Elapsed
Size Size Size Time Throughput
bytes bytes bytes secs. 10^6bits/sec

87380 16384 16384 14.00 6.05

-> after patch :

Recv Send Send
Socket Socket Message Elapsed
Size Size Size Time Throughput
bytes bytes bytes secs. 10^6bits/sec

87380 16384 16384 10.00 18509.73


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