Great! Im testing it right now. Yes, it will be nice to see the maths involved in the 'utilization %' calculations.
Thanks! Gerardo ----- Mensaje original ----- > De: "Marek Becka" <[email protected]> > Para: [email protected] > Enviados: Viernes, 3 de Julio 2015 11:52:47 > Asunto: Re: [collectd] question about new "disk" metrics > > On 06/16/2015 11:12 AM, Markus "Shorty" Uckelmann wrote: > > Am 16.06.2015 um 06:32 schrieb Markus "Shorty" Uckelmann: > >> Am 16.06.2015 um 00:20 schrieb Gerardo Herzig: > >>> Hi all. Im trying to use the "disk" metrics of the new 5.5 > >>> colletcd version, in order to avoid the "iostat" ruby wraper. > >>> What is cool about "iostat -x" is the "disk util%", to knowing > >>> how stressed the disk are. > >> > >>> So, it is not clear to me what maths are involved in that > >>> calculations. Anyone knows if it is possible now with the new > >>> disk-plugin metrics? > >> > >> Under Linux it should (sorry, haven't checked the code) derive > >> from > >> the iostats utility. From the man page: > >> > >> %util Percentage of elapsed time during which I/O requests were > >> issued to the device (bandwidth utilization for the device). > >> Device > >> saturation occurs when this value is close to 100% for devices > >> serving requests serially. But for devices serving requests in > >> parallel, such as RAID arrays and modern SSDs, this number does > >> not > >> reflect their performance limits. > > > > Mea culpa! I just didn't read your post correctly. I can't answer > > your > > questions. > > > > So far I was able to find the "weighted_time" variable in the code > > of > > disk.c. This should be the last field from /proc/diskstats which > > contains the utilization as described above. But I'm not sure what > > happens to this metric (my C is bad). Because it doesn't show up in > > the output of the plugin. > > > > So someone with knowledge of that plugin might jump in. I would be > > interested in the disk utilisation too ;) > > > > BTW: Some interesting links I found: > > > > http://www.mjmwired.net/kernel/Documentation/iostats.txt > > http://www.xaprb.com/blog/2010/01/09/how-linux-iostat-computes-its-results/ > > > > https://stackoverflow.com/questions/4458183/how-the-util-of-iostat-is-computed > > > > > > > > Hi, I'm using own patch for disk plugin that adds disk utilization > and > number of in-flight requests. I didn't request pull to the upstream > yet. The patch can be found at > https://github.com/marekbecka/collectd/pull/1 > > > > _______________________________________________ > collectd mailing list > [email protected] > http://mailman.verplant.org/listinfo/collectd > _______________________________________________ collectd mailing list [email protected] http://mailman.verplant.org/listinfo/collectd
