From: Andrew Lunn <andrew@lunn.ch>
To: J?rgen Lambrecht <J.Lambrecht@televic.com>
Cc: eCos Discussion <ecos-discuss@ecos.sourceware.org>,
J?rgen Lambrecht <jurgen.lambrecht@scarlet.be>
Subject: Re: [ECOS] max IP packet size = 9216 B. Why?
Date: Tue, 12 Jun 2007 22:12:00 -0000 [thread overview]
Message-ID: <20070612160753.GP26816@lunn.ch> (raw)
In-Reply-To: <466EC08A.8090704@televic.com>
On Tue, Jun 12, 2007 at 05:49:30PM +0200, J?rgen Lambrecht wrote:
> Hello,
>
> I found out that the maximum IP packet size = 9216 B (0x2400).
> I implemented an echo program, both udp and tcp.
> My ecos applic can receive more that 9216B, but not send back more than
> that.
>
> Has anybody a clue how to solve this?
> I need to support the maximum IP packet size of 65535 B (IP_MAXPACKET).
Interesting. What network technology do you have underneath
this. Something reliable i presume since even small packet error rates
are going to cause big delay and inefficiencies with retries.
> I don't know if this is a bug in ecos, or a (hidden?) limitation of an
> embedded OS.
I don't know of anybody else using nearly jumbo packets. So you might
be running into bugs, or configuration tweaks might be needed.
> I'm busy tracing this back in the source
> This comes from the socket that is allocated statically in
> /io/fileio/.../fd.cxx and socket is part of a cyg_file (cyg_file is
> defined by file in file.h). In cyg_file there is a member f_data, which
> is the socket.
> I'm continuing my search in the code at this point....
Do you get a crash, or does write/sendto return an error code?
Andrew
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next prev parent reply other threads:[~2007-06-12 16:08 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-06-12 21:58 Jürgen Lambrecht
2007-06-12 22:12 ` Andrew Lunn [this message]
2007-06-12 22:46 ` Jürgen Lambrecht
2007-06-12 23:03 ` Andrew Lunn
2007-06-13 14:24 ` Jürgen Lambrecht
2007-06-13 15:44 ` Andrew Lunn
[not found] ` <058cebc1-1c19-438d-b5de-2c8015835c36@googlegroups.com>
2017-06-20 10:29 ` Jürgen Lambrecht
2017-06-23 10:32 ` Jürgen Lambrecht
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