Re: [PATCH 1/1] tcp: Wrong timeout for SYN segments

From: Eric Dumazet
Date: Sat Aug 25 2012 - 05:01:46 EST



> From: Alexander Bergmann <alex@xxxxxxxxxx>
> Date: Fri, 24 Aug 2012 14:09:49 +0200
> Subject: [PATCH 1/1] tcp: Increase timeout for SYN segments
>
> Commit 9ad7c049 changed the initRTO from 3secs to 1sec in accordance to
> RFC6298 (former RFC2988bis). This reduced the time till the last SYN
> retransmission packet gets sent from 93secs to 31secs.
>
> RFC1122 is stating that the retransmission should be done for at least 3
> minutes, but this seems to be quite high.
>
> "However, the values of R1 and R2 may be different for SYN
> and data segments. In particular, R2 for a SYN segment MUST
> be set large enough to provide retransmission of the segment
> for at least 3 minutes. The application can close the
> connection (i.e., give up on the open attempt) sooner, of
> course."
>
> This patch increases the value of TCP_SYN_RETRIES to the value of 6,
> providing a retransmission window of 63secs.
>
> The comments for SYN and SYNACK retries have also been updated to
> describe the current settings.
>
> Signed-off-by: Alexander Bergmann <alex@xxxxxxxxxx>
> ---

Acked-by: Eric Dumazet <edumazet@xxxxxxxxxx>


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/