Garrett Wollman wrote: > <<On Tue, 12 Mar 2013 23:48:00 -0400 (EDT), Rick Macklem > <rmack...@uoguelph.ca> said: > > > Basically, this patch: > > - allows setting of the tcp timeout via vfs.nfsd.tcpcachetimeo > > (I'd suggest you go down to a few minutes instead of 12hrs) > > - allows TCP caching to be disabled by setting vfs.nfsd.cachetcp=0 > > - does the above 2 things you describe to try and avoid the > > livelock, > > although not quite using an lru list > > - increases the hash table size to 500 (still a compile time > > setting) > > (feel free to make it even bigger) > > - sets nfsrc_floodlevel to at least nfsrc_tcphighwater, so you can > > grow vfs.nfsd.tcphighwater as big as you dare > > Thanks, this looks very good. One quibble with the last bit: I'd do > that in a sysctl() handler rather than checking it every time through. > If somebody uses a debugger rather than sysctl to change tcphighwater, > they deserve what's coming to them. Also, I might suggest adding a > counter for how many times we had to go through the "try harder" > phase, so that the sysadmin has some indication that the defaults need > adjustment. > I agree w.r.t. both comments. I did the one line setting of nfsrc_floodlevel, just because I was getting lazy while doing the patch.
And if/when a patch like this (I think if this works, it can easily be added to ivoras@'s patch) goes into head, some way for a sysadmin to monitor how well it's working would be good. A count of the "try harder" attempts seems like a good candidate. Good luck with testing of it, rick > I will test this out later this week and see how it performs. I have > a user who has been able to reproducibly clobber servers before, so if > he has time and cycles available it should be pretty easy to tell > whether it's working or not. > > -GAWollman _______________________________________________ freebsd-net@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
