On Wed, Jan 29, 2014 at 1:27 PM, Michael Richardson <[email protected]> wrote: > > I often run rsync over ssh to transfer files. > I suspect that they are being classified wrong, and are competing with my > interactive ssh sessions. I experience classic bufferbloat issues with a > congested uplink when typing. (But, DNS and web is unaffected, it seems)
0) you should measure your delay and post... 1) I switched to mosh for most of my interactive sessions that I used to use ssh for. Helps. 2) there are patches to rsync to use a different cc algo and diffserv marking, but those only work over native tcp. https://git.samba.org/?p=rsync-patches.git;a=blob_plain;f=congestion.diff;hb=master > > I notice in ssh_config(5) man page that it says: > > IPQoS Specifies the IPv4 type-of-service or DSCP class for > connections. Accepted values are ``af11'', > ``af12'', ``af13'', ``af21'', ``af22'', ``af23'', ``af31'', > ``af32'', ``af33'', ``af41'', ``af42'', > ``af43'', ``cs0'', ``cs1'', ``cs2'', ``cs3'', ``cs4'', ``cs5'', > ``cs6'', ``cs7'', ``ef'', ``lowdelay'', > ``throughput'', ``reliability'', or a numeric value. This > option may take one or two arguments, sepa- > rated by whitespace. If one argument is specified, it is used > as the packet class unconditionally. If > two values are specified, the first is automatically selected > for interactive sessions and the second > for non-interactive sessions. The default is ``lowdelay'' for > interactive sessions and ``throughput'' > for non-interactive sessions. 3) I don't think rsync currently tries to set anything when using ssh as a transport. Perhaps those patches can be improved to pass it down to the ssh call? > > > I can see no evidence that my IPv6 packets are being changed in anyway. A lot of systems don't have the correct IPV6_TCLASS call. > On IPv4, I see: > > 16:25:50.744290 IP (tos 0x8, ttl 64, id 62723, offset 0, flags [DF], proto > TCP (6), length 52) > 209.87.252.250.51417 > 97.107.133.15.22: Flags [F.], cksum 0x5735 > (correct), seq 623906, ack 3314, win 110, options [nop,nop,TS val 1178738167 > ecr 2623900673], length 0 > > I'm not sure that "tos 0x8" is particularly useful. It's DSCP 1, and I think > it's actually being marked TOS-like. Your rsync over ssh should get marked background (CS1) somehow, and ssh interactive, interactive. openssh has different behavior than dropbear. Dropbear only recently added some support for saner classification. > Will any value here have any affect on default 3.10 qos.sh script? > -- > ] Never tell me the odds! | ipv6 mesh networks [ > ] Michael Richardson, Sandelman Software Works | network architect [ > ] [email protected] http://www.sandelman.ca/ | ruby on rails > [ > > > > > _______________________________________________ > Cerowrt-devel mailing list > [email protected] > https://lists.bufferbloat.net/listinfo/cerowrt-devel -- Dave Täht Fixing bufferbloat with cerowrt: http://www.teklibre.com/cerowrt/subscribe.html _______________________________________________ Cerowrt-devel mailing list [email protected] https://lists.bufferbloat.net/listinfo/cerowrt-devel
