DragonFly kernel List (threaded) for 2011-07
Re: Blogbench RAID benchmarks
On Tue, Jul 12, 2011 at 09:09:58AM -0700, Matthew Dillon wrote:
> blogbench --iterations=200 ... and you really need to include the
> actual blogbench output. The final results are worthless.
I had not enough time to do long benchmarks on the machine anymore.
Howewer, I can now use another one with only 4GB memory. How many iterations
do you think would be enough to do a good test with this quantity of RAM ?
> Linear write activity. I wonder why it isn't
> clustering the I/O's, though.
That was newfs_hammer
> Try setting vfs.hammer.double_buffer=1.
Will do in a future test.
> : 0 3 15.94 288 4.48 1 0 85 0 14
> : 0 3 16.00 620 9.69 1 0 79 0 20
> : 0 3 16.00 352 5.50 1 0 84 0 15
> This doesn't look good either. It shouldn't degrade that much,
> though it's a bit hard to tell with iostat because it doesn't print
> the disk busy %.
What could I use to get meaningful data ?