Re: [PATCH] tcp_cubic: limit delayed_ack ratio to prevent divide error

Brandeburg, Jesse
2011-05-04T20:54:03Z

On Wed, 4 May 2011, Stephen Hemminger wrote:

> TCP Cubic keeps a metric that estimates the amount of delayed
> acknowledgements to use in adjusting the window. If an abnormally
> large number of packets are acknowledged at once, then the update
> could wrap and reach zero. This kind of ACK could only
> happen when there was a large window and huge number of
> ACK's were lost.
>
> This patch limits the value of delayed ack ratio. The choice of 32
> is just a conservative value since normally it should be range of
> 1 to 4 packets.
>
> Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>

patch seems fine, but please credit the reporter (lkml@techboom.com) with
reporting the issue with logs, maybe even with Reported-by: and some kind
of reference to the panic message or the email thread in the text or
header?