DragonFly kernel List (threaded) for 2011-07
Re: Blogbench RAID benchmarks
:> writes: 600
:> reads : 178372
:For good measure, I did the same test with UFS1+softupdates.
:The results are much lower:
: writes: 282
: reads: 20522
:there was very little disk activity and blogbench was almost constantly
:sleeping (process in nanslp state)
There's something very basic wrong. How much memory does the machine
have? Blogbench clearly isn't running long enough to blow out the
system caches. Try more iterations:
Otherwise you aren't testing the disk drives at all.
w/regards to the CAM fix, to determine if it is meaningful use
/usr/src/test/sysperf/randread.c. The default parameters should be
sufficient. Run it on the raw disk block device (it should work for
FreeBSD too but I'm not sure lseek will properly size the drive).
Serialized disk reads will show up at around ~150-200 tps. Multi-tagged
disk reads will show up in the 400-500 tps range.