Hi Matt: My $0.02 is to look at rrdcached if you are concerned about I/O, it has done wonders to lower the load on servers running RRDtool updates on a lot of RRD files.
Cheers, Bernard On Fri, Sep 24, 2010 at 11:44 AM, Matt Kassawara <mkassaw...@gmail.com> wrote: > My organization wants to record more detailed information for longer > periods of time without consuming excessive resources on the server > performing RRD operations and storing RRD files. I know RRD files > maintain the same size on disk after creation. However, I'm unsure how > the number of RRAs and RRA step/row values affect CPU, disk I/O, and > memory resources particularly during update operations and periodic > internal consolidations. Further complicating the situation, each > graphing application manages RRD files differently. For example, Zenoss > creates one RRD file with a single DS and associated RRAs for each OID > retrieved from a device. Retrieving just a few OIDs from a large number > of devices results in Zenoss operating on many small RRD files per > update cycle. I haven't found a way to configure it otherwise. On the > other hand, Cacti creates one RRD file with a variable number of DS > based on templates. I can configure and implement these templates to > perform roughly the opposite management style of Zenoss by increasing > the size and complexity of each RRD file, but reducing the overall > number of them. I know discussion of Zenoss vs. Cacti wanders > off-topic, but in this case providing the methods they use for managing > RRD files may greatly affect answers to my primary question. > > I currently use Zenoss to retrieve about 11000 OIDs every 5 minutes. > Each of the 11000 RRD files contains 4 RRAs providing data for about 2 > days at 5 minute intervals (essentially no consolidation), 2 weeks at 30 > minute intervals, 50 days at 2 hour intervals, and 600 days at 1 day > intervals. > > What sort of effects on CPU, disk I/O, and memory resources can I > anticipate during update and periodic internal consolidations if, for > example, I change these RRAs to 1 year at 5 minute intervals > (essentially no consolidation), 2 years at 1 hour intervals, and 3 years > at 1 day intervals? Can anyone provide a formula or general way to > estimate resource consumption for various RRA configurations? When > confronting resource issues, which forms of RRD tuning (e.g., increasing > RRA steps, reducing RRA rows, or even eliminating RRAs) provide the most > effect? I'm also somewhat interested in determining how various RRA > configurations might affect resources needed for graph operations. > > Thanks, > Matt > > _______________________________________________ > rrd-users mailing list > rrd-users@lists.oetiker.ch > https://lists.oetiker.ch/cgi-bin/listinfo/rrd-users > _______________________________________________ rrd-users mailing list rrd-users@lists.oetiker.ch https://lists.oetiker.ch/cgi-bin/listinfo/rrd-users