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Date: Tue, 05 Nov 2013 11:10:26 +0100
From: Olivier MATZ <olivier.matz@6wind.com>
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Cc: "dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] Surprisingly high TCP ACK packets drop counter
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Hi,

 > Disabling RSC (DPDK 1.3) indeed brings ACK flood forwarding
 > performance to 14,5+ Mpps. No negative side affects were discovered
 > so far, but we're still testing.

The role of RSC is to reassemble input TCP segments, so it is possible
that the number of TCP packets sent to the DPDK is lower but some
packets may contain more data. Can you confirm that?

In my opinion, this mechanism should be disabled by default because it
could break PMTU discovery on a router. However it could be useful for
somebody doing TCP termination only.

Regards,
Olivier