On Sat, Aug 25, 2012 at 1:48 AM, Alexander Bergmann <a...@linlab.net> wrote: > On Fri, Aug 24, 2012 at 01:42:31PM -0400, David Miller wrote: >> Alex, this patch doesn't apply, it was completely corrupted by your email >> client. >> >> Make a fresh submission, with this fixed. But before you do, email the >> patch to yourself and make sure you can actually apply the patch you >> receive in your inbox. Because that's exactly what I'm going to have >> to do. > > Sorry I messed it up the last time. This time I've double checked as > you suggested. I'll keep that in mind. > > From 11a292b1cff772f930a02fda02d5b741f8ea5033 Mon Sep 17 00:00:00 2001 > From: Alexander Bergmann <a...@linlab.net> > 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 <a...@linlab.net> > --- > include/net/tcp.h | 18 ++++++++++++++---- > 1 files changed, 14 insertions(+), 4 deletions(-) > > diff --git a/include/net/tcp.h b/include/net/tcp.h > index 1f000ff..d43d6b3 100644 > --- a/include/net/tcp.h > +++ b/include/net/tcp.h > @@ -98,11 +98,21 @@ extern void tcp_time_wait(struct sock *sk, int state, int > timeo); > * 15 is ~13-30min depending on RTO. > */ > > -#define TCP_SYN_RETRIES 5 /* number of times to retry active > opening a > - * connection: ~180sec is RFC minimum */ > +#define TCP_SYN_RETRIES 6 /* > + * This is how many retries it does to active > + * opening a connection. > + * RFC1122 says the minimum retry MUST be at > + * least 180secs. Nevertheless this value is > + * corresponding to 63secs of retransmission > + * with the current initial RTO. > + */ > > -#define TCP_SYNACK_RETRIES 5 /* number of times to retry passive opening a > - * connection: ~180sec is RFC minimum */ > +#define TCP_SYNACK_RETRIES 5 /* > + * This is how may retries it does to passive > + * opening a connection. > + * This is corresponding to 31secs of > + * retransmission with the current initial > RTO.
IMHO 31secs seem a little short. Why not change it to 6 as well because 63 secs still beats 93secs with 3sec initRTO and 5 retries. Jerry > + */ > > #define TCP_TIMEWAIT_LEN (60*HZ) /* how long to wait to destroy TIME-WAIT > * state, about 60 seconds */ > -- > 1.7.8.6 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
