From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <8803e7b955b023baa49ec12012579323@coraid.com>
From: erik quanstrom <quanstro@coraid.com>
Date: Mon, 22 Jan 2007 13:34:59 -0500
To: 9fans@cse.psu.edu
Subject: Re: [9fans] snoopy oddity
In-Reply-To: <ee9e417a0701220854o14267e7eoa5e5812a57512794@mail.gmail.com>
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so i would assume that this isn't going to work very well for
high bandwidth, scaled tcp connections?

- erik

On Mon Jan 22 11:56:17 EST 2007, rsc@swtch.com wrote:
> > has anyone seen snoopy miss packets like this?  i see the ack for a packet
> > that snoopy never sees.  these hosts are connected back-to-back.
>
> sure.  if snoopy isn't reading packets out of the kernel fast enough,
> it will miss some.  the kernel can't buffer them up indefinitely.
>
> for the size of the buffer:
>
> if you are reading from a snoop file then see
> /sys/src/9/ip/ipifc.c:319 (arg to qopen).
>
> if you are reading from an ether device then see
> /sys/src/9/pc/devether.c:428,440 (arg to netifinit)
>
> russ