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From: Shlomo Pongartz <shlomop@mellanox•com>
To: Rick Jones <rick.jones2@hp•com>
Cc: Eric Dumazet <eric.dumazet@gmail•com>,
	"netdev@vger•kernel.org" <netdev@vger•kernel.org>
Subject: Re: GRO aggregation
Date: Thu, 13 Sep 2012 09:36:49 +0300	[thread overview]
Message-ID: <50517F01.9050501@mellanox.com> (raw)
In-Reply-To: <5050BDB5.8090200@hp.com>

On 9/12/2012 7:52 PM, Rick Jones wrote:
> On 09/12/2012 09:34 AM, Shlomo Pongartz wrote:
>> On 9/12/2012 7:23 PM, Rick Jones wrote:
>>> On 09/12/2012 07:41 AM, Shlomo Pongartz wrote:
>>>> Hi Eric
>>>>
>>>> The TSO is just a mean to create a burst of frames on the wire so the
>>>> NAPI will be able to pool as much as possible.
>>>
>>> Is it?  If I recall correctly, TSO was in place well before all
>>> drivers were using NAPI.  And NAPI was being proposed independent of
>>> TSO. TSO is there to save CPU cycles on the transmit side. "On the
>>> wire" what it sends is to be identical to what a host with greater CPU
>>> performance could accomplish.
>>>
>>> rick jones
>>>
>> Hi Rick.
>>
>> What I say is that I use TSO on the machine that transmits so I'll have
>> a burst of frames on the wire for the NAPI on the receiver machine.
>
> Also, NAPI was in place before GRO.  IIRC, the napi code was simply a 
> convenient/correct/natural place to have the GRO functionality.
>
> rick jones
>
Hi Rick

The thing is that napi_complete calls napi_gro_flush so this pose a 
limit on the aggregation.
However when I count the number of packets received until this routine 
is been called, I get a number,
which is bigger then what I see with tcpdump, and this number is less 
than what is expected if the limit is 64K.
So I what to know what can I do in order to improve things, e.g. 
allocate the skb differently.

Shlomo

  reply	other threads:[~2012-09-13  6:37 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-09-11 13:45 GRO aggregation Shlomo Pongartz
2012-09-11 18:20 ` Marcelo Ricardo Leitner
2012-09-11 18:41   ` Shlomo Pongratz
2012-09-11 18:48     ` Marcelo Ricardo Leitner
2012-09-11 18:51       ` Shlomo Pongratz
2012-09-11 18:33 ` Eric Dumazet
2012-09-11 18:49   ` Shlomo Pongratz
2012-09-11 19:01     ` Eric Dumazet
2012-09-11 19:24       ` Shlomo Pongratz
2012-09-11 19:35         ` David Miller
2012-09-11 19:35         ` Eric Dumazet
2012-09-12  9:23           ` Shlomo Pongartz
2012-09-12  9:33             ` Eric Dumazet
2012-09-12 14:41               ` Shlomo Pongartz
2012-09-12 16:23                 ` Rick Jones
2012-09-12 16:34                   ` Shlomo Pongartz
2012-09-12 16:52                     ` Rick Jones
2012-09-13  6:36                       ` Shlomo Pongartz [this message]
2012-09-13  8:11                         ` Eric Dumazet
2012-09-13  9:59                           ` Or Gerlitz
2012-09-13 12:05                             ` Eric Dumazet
2012-09-13 12:34                               ` Eric Dumazet
2012-09-13 12:47                               ` Or Gerlitz
2012-09-13 13:22                                 ` Eric Dumazet

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