From: "Johann Baudy" <johaahn@gmail.com>
To: "Evgeniy Polyakov" <johnpol@2ka.mipt.ru>
Cc: netdev@vger.kernel.org
Subject: Re: Fwd: Packet mmap: TX RING and zero copy
Date: Fri, 5 Sep 2008 15:55:14 +0200 [thread overview]
Message-ID: <7e0dd21a0809050655n176ec32bo2bf4febe4e0fc363@mail.gmail.com> (raw)
In-Reply-To: <20080905133748.GA28656@2ka.mipt.ru>
Hi Evgeniy,
> That's a bug. Likely no one sends file content via udp, so it was not
> detected...
Ok, I'll will run a FTRACE of this issue on monday;
>> I will try to investigate it but for my app sendfile() is not
>> conceivable. Only vmsplice could, but too slow.
>
> Well, you can mmap empty file into the RAM, lock it there, DMA data from
> the sensor to the mmapped area, add headers (just in the mapped area)
> and then sendfile that file.. Single syscall, zero-copy, standard
> interfaces :)
>
OK but it seems that there is no way to control packet format.
(beginning of packet and size of packet).
Each packet must start with a specific header (on my app). This is a
kind of streaming.
Thanks,
Johann
--
Johann Baudy
johaahn@gmail.com
next prev parent reply other threads:[~2008-09-05 13:55 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-09-02 18:27 Packet mmap: TX RING and zero copy Johann Baudy
2008-09-02 19:46 ` Evgeniy Polyakov
2008-09-03 7:56 ` Johann Baudy
2008-09-03 10:38 ` Johann Baudy
2008-09-03 11:06 ` David Miller
2008-09-03 13:05 ` Johann Baudy
2008-09-03 13:27 ` Evgeniy Polyakov
2008-09-03 14:57 ` Christoph Lameter
2008-09-03 15:00 ` Johann Baudy
2008-09-03 15:13 ` Evgeniy Polyakov
2008-09-03 15:58 ` Johann Baudy
2008-09-03 16:43 ` Evgeniy Polyakov
2008-09-03 20:30 ` Johann Baudy
2008-09-03 22:03 ` Evgeniy Polyakov
2008-09-04 14:44 ` Johann Baudy
2008-09-05 7:17 ` Evgeniy Polyakov
[not found] ` <7e0dd21a0809050216r65b8f08fm1ad0630790a13a54@mail.gmail.com>
2008-09-05 9:17 ` Fwd: " Johann Baudy
2008-09-05 11:31 ` Evgeniy Polyakov
2008-09-05 12:44 ` Johann Baudy
2008-09-05 13:16 ` Evgeniy Polyakov
2008-09-05 13:29 ` Johann Baudy
2008-09-05 13:37 ` Evgeniy Polyakov
2008-09-05 13:55 ` Johann Baudy [this message]
2008-09-05 14:19 ` Evgeniy Polyakov
2008-09-05 14:45 ` Johann Baudy
2008-09-05 14:59 ` Evgeniy Polyakov
2008-09-05 15:30 ` Johann Baudy
2008-09-05 15:38 ` Evgeniy Polyakov
2008-09-05 16:01 ` Johann Baudy
2008-09-05 16:34 ` Evgeniy Polyakov
2008-09-08 10:21 ` Johann Baudy
2008-09-08 11:26 ` Evgeniy Polyakov
2008-09-08 13:01 ` Johann Baudy
2008-09-08 15:28 ` Evgeniy Polyakov
2008-09-08 15:38 ` Evgeniy Polyakov
2008-09-09 23:11 ` Johann Baudy
2008-09-10 6:09 ` Evgeniy Polyakov
2008-09-05 10:28 ` Robert Iakobashvili
2008-09-05 13:06 ` Johann Baudy
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