>On Sat, 5 Apr 2014, Greg Troxel wrote: > >> <snip> >> >> I see no fails counted. Why do you think you are out of clusters? >Are >> you seeing that in dmesg? Or is it just a possible lockup >explanation? > >The mbuf/mbufcluster "explanation" was offered when I first reported >this several months ago. > >> Please describe the lockup symptoms more precisely. > >Most obvious symptom is sudden lack of network connectivity. A ping to > >another host on the local network fails with a "no buffer space" error. > >> Also, look in vmstat -m for anything with fail != 0. > >No failures ever appear. > >However, I have tracked mbuf usage via netstat and vmstat, and shortly >before the lockup, both numbers showed a sudden increase in >utilization. > >> you might also save vmstat -m to a file every 5 minutes, and look >> before/after the next lockup. > >Yeah, I was doing this every 1 minute... > > >Someone at that time suggested that bit-torrent could have been doing >something nasty, so I stopped my "transmission" server. The frequency >of lockup has dropped dramatically, but not to zero. > > >Another symptom is with postfix... It receives incoming mail from the >network, but fails to forward the mail through my local dspam - mailq >shows lots of messages in the "deferred" state due to "resources
> > > > > >------------------------------------------------------------------------- >| Paul Goyette | PGP Key fingerprint: | E-mail addresses: >| >| Customer Service | FA29 0E3B 35AF E8AE 6651 | paul at whooppee.com >| >| Network Engineer | 0786 F758 55DE 53BA 7731 | pgoyette at juniper.net >| >| Kernel Developer | | pgoyette at netbsd.org >| >------------------------------------------------------------------------- On 6. April 2014 18:50:28 MESZ, Paul Goyette <[email protected]> wrote: >temporarily unavailable" errors. (As near as I can tell, postfix uses >unix-family sockets for this...) ...i can notice the same scenario with the same error msgs in timeframes of weeks on a xen virtualized machine (seems only a NetBSD over 6.x is affected) with several TCP services plus DNS plus local unix sockets - but i have no "blocked" unix sockets before and even when the net "goes down" seconds or minutes before the os locks completely. On xen i had an additional effect - if i tried to define a second network interface for local (host internal) LAN TCP connections to the local LAN brought down the other interface traffic too. Not shure if this is related - the behaviours are very similiar to the mbuf network slowdown/lock before system lock. I do not understand in detail why the whole OS is locking in a case where mbufs are going out - if a system i.e. goes out of file descriptors the os byself is still reacting. So is this a bug or feature? ß) hth cheerioh, Niels. -- Niels Dettenbach Syndicat IT&Internet http://www.syndicat.com
