Le 30 sept. 2013 à 20:09, Ronald Roskens <rosk...@elfin.net> a écrit : > > I've got 162GB of rrd on a host with 72GB of ram, and update the files every > 5 minutes also. The system has a lot of I/O going on, and its able to keep up > writing the data out. The point is that every time you want to update a > single file, there is too much read overhead associated with opening the file > just to write out a single update and close the file. > > I've wondered if you were to implement something like storeByGroup, but for > all metrics under the node (storeByNode?) and have it pre-allocate a specific > size whether you could take advantage then of being able to keep the RRDs > open (and thus limit the read hits). So you would see something like: > > share/rrd/1/ > files.properties > rrd-types.properties > base1-chunk1.rrd > base2-chunk1.rrd > > rrd-types.properties would map the <rrd><rra>…</rrd> blocks to the baseX > prefixes. > > files.properties would map the the path & datasources to the specific chunk > files. The chunk files would pre-allocate 50-100 datasources each. > > If you were able to store more datasources into these files, then the rrd > strategy wouldn't need to open/close the files for each update. It could take > advantage of the RrdDbPool and keep the files open. > > Ron >
The backend api in jrobin/rrd4j is very poor, as it provides access only to raw bytes. I'm trying to change that with rrd4j v3, where the api provides access to higher level functions: header, rra, ds. The abstract class to implement to can be found at https://code.google.com/p/rrd4j/source/browse/?name=NewBackEnd#git%2Fsrc%2Fmain%2Fjava%2Forg%2Frrd4j%2Fbackend%2Fspi So it should be easier to play with new ideas. ------------------------------------------------------------------------------ October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register > http://pubads.g.doubleclick.net/gampad/clk?id=60133471&iu=/4140/ostg.clktrk _______________________________________________ Please read the OpenNMS Mailing List FAQ: http://www.opennms.org/index.php/Mailing_List_FAQ opennms-devel mailing list To *unsubscribe* or change your subscription options, see the bottom of this page: https://lists.sourceforge.net/lists/listinfo/opennms-devel
