Joshua Berkus <j...@agliodbs.com> Friday 15 April 2011 18:55:04 > Radoslaw, > > 10% improvement isn't very impressive from a switch to mmap. What workload > did you test with? What I'd really like to see is testing with databases > which are 50%, 90% and 200% the size of RAM ... that's where I'd expect > the greatest gain from limiting copying. I think 10% is quite good, as my stand-alone test of mmap vs. read shown that speed up of copying 100MB data to mem may be from ~20ms to ~100ms (depends on destination address). Of course deeper, system test simulating real usage will say more. In any case after good deals with writes, I will speed up reads. I think to bypass smgr/md much more and to expose shared id's (1,2,3...) for each file segment.
Going to topic... In attachment I sent test-scripts which I used to fill data, nothing complex (left from 2nd level caches). Query I've used to measure was SELECT count(substr(content, 1, 1)) FROM testcase1 WHERE multi_id > 50000; Timings ware taken from psql. I didn't made load (I have about 2GB of free sapce at /home, and 4GB RAM) and stress (I'm not quite ready to try concurrent updates of same page - may fail, notice is and place to fix is in code) tests yet. > > Netbeans is possibly not very well suited to working on postgres code. > > AFAIK emacs and/or vi(m) are used by almost all the major developers. > > Guys, can we *please* focus on the patch for now, rather than the > formatting, which is fixable with sed? Netbeans is quite good, of course it depends who likes what. Just try 7.0 RC 2. Regards, Radek
test-scritps_20110319_0026.tar.bz2
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