I guess poll is not an option??? :-(
I would REALLY like poll, but I am not a C programmer... :-( Dave http://netmgt.blogspot.com/ Sent from my iPhone On Apr 13, 2012, at 7:00 AM, Stian Øvrevåge <[email protected]> wrote: > Found this handy anecdote on http://collectd.org/wiki/index.php/Plugin:SNMP > > "Maximum number of hosts > While collectd and the SNMP plugin don't have any limitation on the > number of hosts you can configure, the library used by the SNMP > plugin, libnetsnmp, uses the select(2) system call. This system call > uses a fixed-size bitfield to hold file descriptors. On many systems > this limits the number of hosts you can query with the SNMP plugin to > 1024 (for example when using the GNU libc). > > To solve this issue, the netsnmp library must be changed. A solution > would be to switch to the poll(2) system call which doesn't have a > static limit on the largest file descriptor it can handle." > > So my current work-around and using several collectd processes seems > to be a permanent one :-) > > Brgds > Stian Øvrevåge > > On Thu, Apr 12, 2012 at 11:21, Stian Øvrevåge <[email protected]> wrote: >> Hi list, >> >> Banging my head against the wall for weeks now trying to get a working >> medium scale collectd-installation working... >> >> I thought I had fixed the max number of sockets/connecting when tuning >> /etc/security/limits.conf. It now reads: >> >> ulimit -n >> 32768 >> >> I have the instances of collectd now. One of them is set to poll 2300 >> hosts. Of which an unknown number is offline at any time. I'm watching >> strace as well as netstat and everything seems fine and "netstat -anop >> udp|wc -l" counts the number of udp sockets created until the number >> hits about 1092. Here it stalls and syslog logs thousand lines of >> >> "Apr 12 11:07:41 collectd-new collectd[1488]: snmp plugin: host >> x.y.z: snmp_sess_synch_response failed:" >> >> within a few seconds. Number of UDP sockets from then on are stable. >> >> If I also start the other two instances the number of sockets grows to >> 1292. Which leads me to believe that there is a per-process(or >> thread?) limit somewhere. >> >> Information on the internet on the issue is scarce other than the file >> descriptor limit which I believe is unrelated. >> >> Regards, >> Stian Øvrevåge > > _______________________________________________ > collectd mailing list > [email protected] > http://mailman.verplant.org/listinfo/collectd _______________________________________________ collectd mailing list [email protected] http://mailman.verplant.org/listinfo/collectd
