From mboxrd@z Thu Jan 1 00:00:00 1970 From: Olivier MATZ Subject: Re: Surprisingly high TCP ACK packets drop counter Date: Tue, 05 Nov 2013 11:10:26 +0100 Message-ID: <5278C412.4000204@6wind.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: "dev-VfR2kkLFssw@public.gmane.org" To: Alexander Belyakov Return-path: In-Reply-To: List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces-VfR2kkLFssw@public.gmane.org Sender: "dev" 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