Messages in this thread | | | From | Jeff Moyer <> | Subject | Re: Performance regression in IO scheduler still there | Date | Wed, 11 Nov 2009 12:43:30 -0500 |
| |
Jan Kara <jack@suse.cz> writes:
> Sadly, I don't see the improvement you can see :(. The numbers are the > same regardless low_latency set to 0: > 2.6.32-rc5 low_latency = 0: > 37.39 36.43 36.51 -> 36.776667 0.434920 > But my testing environment is a plain SATA drive so that probably > explains the difference...
I just retested (10 runs for each kernel) on a SATA disk with no NCQ support and I could not see a difference. I'll try to dig up a disk that support NCQ. Is that what you're using for testing?
Cheers, Jeff
2.6.29 2.6.32-rc6,low_latency=0 ---------------------------------- Average: 34.6648 34.4475 Pop.Std.Dev.: 0.55523 0.21981
| |