Re: svn commit: r242261 - head/sys/netinet
On 28 Oct 2012, at 12:02, Andre Oppermann an...@freebsd.org wrote: Author: andre Date: Sun Oct 28 19:02:07 2012 New Revision: 242261 URL: http://svn.freebsd.org/changeset/base/242261 Log: For retransmits of SYN|ACK from the syncache use the slightly more aggressive special tcp_syn_backoff[] retransmit schedule instead of the normal tcp_backoff[] schedule for established connections. How did you came up with the values for tcp_syn_backoff? I obviously understand the aggressiveness, but did you measure any significant improvement in connection establishment time and if so, on what type of links? Regards, -- Rui Paulo ___ svn-src-head@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to svn-src-head-unsubscr...@freebsd.org
Re: svn commit: r242261 - head/sys/netinet
On 28.10.2012 22:34, Rui Paulo wrote: On 28 Oct 2012, at 12:02, Andre Oppermann an...@freebsd.org wrote: Author: andre Date: Sun Oct 28 19:02:07 2012 New Revision: 242261 URL: http://svn.freebsd.org/changeset/base/242261 Log: For retransmits of SYN|ACK from the syncache use the slightly more aggressive special tcp_syn_backoff[] retransmit schedule instead of the normal tcp_backoff[] schedule for established connections. How did you came up with the values for tcp_syn_backoff? I obviously understand the aggressiveness, but did you measure any significant improvement in connection establishment time and if so, on what type of links? I didn't come up with the values. tcp_syn_backoff[] was introduced almost 12 years ago by jlemon. For syncache it got lost somewhere along the line. There has been recent talk by some large FreeBSD web server operators of reducing SYN|ACK retransmit timeouts. This change fixes a part of the problem. The recent RFC on reducing the RTO will fix the other part. -- Andre ___ svn-src-head@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to svn-src-head-unsubscr...@freebsd.org
Re: svn commit: r242261 - head/sys/netinet
On Oct 28, 2012, at 14:56, Andre Oppermann an...@freebsd.org wrote: On 28.10.2012 22:34, Rui Paulo wrote: On 28 Oct 2012, at 12:02, Andre Oppermann an...@freebsd.org wrote: Author: andre Date: Sun Oct 28 19:02:07 2012 New Revision: 242261 URL: http://svn.freebsd.org/changeset/base/242261 Log: For retransmits of SYN|ACK from the syncache use the slightly more aggressive special tcp_syn_backoff[] retransmit schedule instead of the normal tcp_backoff[] schedule for established connections. How did you came up with the values for tcp_syn_backoff? I obviously understand the aggressiveness, but did you measure any significant improvement in connection establishment time and if so, on what type of links? I didn't come up with the values. tcp_syn_backoff[] was introduced almost 12 years ago by jlemon. For syncache it got lost somewhere along the line. Oh, I see. I read it backwards. There has been recent talk by some large FreeBSD web server operators of reducing SYN|ACK retransmit timeouts. This change fixes a part of the problem. The recent RFC on reducing the RTO will fix the other part. Which RFC? I'm only aware of draft-hurtig-tcpm-rtorestart. ___ svn-src-head@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to svn-src-head-unsubscr...@freebsd.org
Re: svn commit: r242261 - head/sys/netinet
On 28.10.2012 23:01, Rui Paulo wrote: On Oct 28, 2012, at 14:56, Andre Oppermann an...@freebsd.org wrote: On 28.10.2012 22:34, Rui Paulo wrote: On 28 Oct 2012, at 12:02, Andre Oppermann an...@freebsd.org wrote: Author: andre Date: Sun Oct 28 19:02:07 2012 New Revision: 242261 URL: http://svn.freebsd.org/changeset/base/242261 Log: For retransmits of SYN|ACK from the syncache use the slightly more aggressive special tcp_syn_backoff[] retransmit schedule instead of the normal tcp_backoff[] schedule for established connections. How did you came up with the values for tcp_syn_backoff? I obviously understand the aggressiveness, but did you measure any significant improvement in connection establishment time and if so, on what type of links? I didn't come up with the values. tcp_syn_backoff[] was introduced almost 12 years ago by jlemon. For syncache it got lost somewhere along the line. Oh, I see. I read it backwards. There has been recent talk by some large FreeBSD web server operators of reducing SYN|ACK retransmit timeouts. This change fixes a part of the problem. The recent RFC on reducing the RTO will fix the other part. Which RFC? I'm only aware of draft-hurtig-tcpm-rtorestart. RFC6298. -- Andre ___ svn-src-head@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to svn-src-head-unsubscr...@freebsd.org
