On Tue, Aug 19, 2008 at 10:49 PM, <david@xxxxxxx> wrote: > On Tue, 19 Aug 2008, Mark Wong wrote: > >> Hi all, >> >> We started an attempt to slice the data we've been collecting in >> another way, to show the results of software vs. hardware RAID: >> >> >> http://wiki.postgresql.org/wiki/HP_ProLiant_DL380_G5_Tuning_Guide#Hardware_vs._Software_Raid >> >> The angle we're trying to show here is the processor utilization and >> i/o throughput for a given file system and raid configuration. I >> wasn't sure about the best way to present it, so this is how it looks >> so far. Click on the results for a chart of the aggregate processor >> utilization for the test. >> >> Comments, suggestions, criticisms, et al. welcome. > > it's really good to show cpu utilization as well as throughput, but how > about showing the cpu utilization as %cpu per MB/s (possibly with a flag to > indicate any entries that look like they may have hit cpu limits) Ok, we'll add that and see how it looks. > why did you use 4M stripe size on the software raid? especially on raid 5 > this seems like a lot of data to have to touch when making an update. I'm sort of taking a shotgun approach, but ultimately we hope to show whether there is significant impact of the stripe width relative to the database blocksize. Regards, Mark
