Hello,
Do you use rrdcached ? If not, use it and all you i/o problem will disappear. Regards, Cyril Le 2013-08-16 00:39, Jesse Reynolds a écrit : > Hello, > > We're noticing some interesting patterns in collectd / librrd is flushing RRD > files to disk. > > We have a 1TB volume for RRD files, which is at 75% capacity. Over the last > few weeks the response time of the disks has slowly degraded, with a few > sudden jumps (see graph below). When it jumps up in response time, it seems > collectd responds by halving the write ops, and octets. Is it just deciding > to flush half as often? If anyone has some pointers to the details of this > behaviour, that'd be great. > > Also, does anyone recognise this pattern as being related to how full the SSD > backed volume is, and perhaps the disks are now needing to do garbage > collection? I'm pretty new to SSDs, and I suspect RRDs are a fairly uncommon > way to utilise SSD drives. > > FWIW, we have 5 x 256 GB Micron SSDs in a IBM hardware RAID 5 set. The OS is > linux (ubuntu 12.04). > > disk time, ms: > https://dl.dropboxusercontent.com/u/5932161/visage/disk%20time%20ms%201%20month.png > [1] > > bytes per second: > https://dl.dropboxusercontent.com/u/5932161/visage/rrd%20disk%20octets%20per%20second%201%20month.png > [2] > > RRD filesystem disk utilisation: > https://dl.dropboxusercontent.com/u/5932161/visage/rrd%20disk%20utilisation%201%20mth.png > [3] > > Thank you! > Jesse > > _______________________________________________ > collectd mailing list > collectd@verplant.org > http://mailman.verplant.org/listinfo/collectd [4] Links: ------ [1] https://dl.dropboxusercontent.com/u/5932161/visage/disk%20time%20ms%201%20month.png [2] https://dl.dropboxusercontent.com/u/5932161/visage/rrd%20disk%20octets%20per%20second%201%20month.png [3] https://dl.dropboxusercontent.com/u/5932161/visage/rrd%20disk%20utilisation%201%20mth.png [4] http://mailman.verplant.org/listinfo/collectd
_______________________________________________ collectd mailing list collectd@verplant.org http://mailman.verplant.org/listinfo/collectd
