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Re: [PATCH] Too aggressive cwnd backoff

To: "David S. Miller" <davem@xxxxxxxxxxxxx>
Subject: Re: [PATCH] Too aggressive cwnd backoff
From: Baruch Even <baruch@xxxxxxxxx>
Date: Thu, 07 Apr 2005 20:18:09 +0100
Cc: shemminger@xxxxxxxx, netdev@xxxxxxxxxxx
In-reply-to: <20050407113351.17f8c094.davem@xxxxxxxxxxxxx>
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David S. Miller wrote:
On Thu, 7 Apr 2005 19:41:46 +0300
Baruch Even <baruch@xxxxxxxxx> wrote:


However, in tcp_cwnd_down we will not stop reducing the cwnd until we
get to limit which is set to tp->ssthresh/2.

The provided patch will set limit to tp->ssthresh. This was the original
behaviour in some older version of Linux.


As stated in another email, it is still unknown where this "changed"
or if it even "changed" at all in the vanilla sources.

Could you track this down?  I still strongly believe this is some
WEB100 change you actually had in your tree, or something like
that.

This change seems to be specific to us (Hamilton), I didn't find it as far back as 2.4.12 [1], it wasn't in any 2.6.x kernel and not even in web100 version alpha 2.3.2 which corresponds to kernel 2.4.23.

It does appear in the original patches that Doug Leith sent, so the only explanation left is that it's something he did in his tree originally. And for some reason I believed it was reverting an old change in the Linux kernel.

Baruch

[1] ftp.ie.kernel.org is missing 2.4.11 and ketchup died in my hands.

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