From: Rick Jones <rick.jones2@hp.com>
To: Eric Dumazet <eric.dumazet@gmail.com>, Rick Jones <raj@tardy.usa.hp.com>
Cc: netdev@vger.kernel.org, davem@davemloft.net
Subject: Re: [PATCH net-next] tcp: Remove some spurious dropped packet profile hits from the passive connection accept path
Date: Thu, 20 Nov 2014 13:31:27 -0800 [thread overview]
Message-ID: <546E5DAF.5090907@hp.com> (raw)
In-Reply-To: <1416516423.8629.43.camel@edumazet-glaptop2.roam.corp.google.com>
On 11/20/2014 12:47 PM, Eric Dumazet wrote:
> On Thu, 2014-11-20 at 10:58 -0800, Rick Jones wrote:
>> From: Rick Jones <rick.jones2@hp.com>
>>
>> When a system is the passive accepter of many connections, for example
>> when the target of a netperf TCP_CC or TCP_CRR test, or as say a web
>> server, the discard of the skb containing the TCP SYN being processed
>> for the LISTEN endpoint should be a consume_skb() rather than a kfree_skb()
>> to avoid cluttering a dropped packet profile.
>>
>> Signed-off-by: Rick Jones <rick.jones2@hp.com>
>>
>> ---
>
> So what happens if we really drop the packet ?
Do you mean when there is actually data in the SYN?
rick
>
> TCP stack at this point owns the packet, it is possible to mark a bit in
> it to either call consume_skb() or kfree_skb()
>
> I attempted this once but gave up because it was a quite intrusive
> patch...
next prev parent reply other threads:[~2014-11-20 21:31 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-11-20 18:58 [PATCH net-next] tcp: Remove some spurious dropped packet profile hits from the passive connection accept path Rick Jones
2014-11-20 20:15 ` Vijay Subramanian
2014-11-20 20:47 ` Eric Dumazet
2014-11-20 21:31 ` Rick Jones [this message]
2014-11-20 21:48 ` Eric Dumazet
2014-11-20 21:51 ` Rick Jones
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