Re: poor sata performance on 2.6

From: Konstantin Sobolev
Date: Thu Apr 15 2004 - 05:54:26 EST


On Thursday 15 April 2004 07:54, Ryan Geoffrey Bourgeois wrote:
> > /dev/hde:
> > Timing buffer-cache reads: 1436 MB in 2.00 seconds = 717.03 MB/sec
> > Timing buffered disk reads: 100 MB in 3.03 seconds = 32.95 MB/sec
> >
> > for sata_sil:
> >
> > /dev/sda:
> > Timing buffer-cache reads: 1412 MB in 2.00 seconds = 705.05 MB/sec
> > Timing buffered disk reads: 84 MB in 3.06 seconds = 27.43 MB/sec
> >
> > So my old IDE HDD appears to be considerably faster. Expected results
> > were 55-70MB/s.
>
> Which kernel version did you get these results using? Have you

Results are the same on different kernels, I tried 2.6.4-ck1 and -ck2,
2.6.4-wolk2.3, 2.6.5 vanilla and 2.6.5-mm5

> speed-tested the drive(s) on a different SATA controller? I don't mean to

Not yet, but I'm going to test it on Intel ICH5 soon.

> imply that you should buy another one - that would be rediculuous since
> your motherboard should laready has it - but it would help to eliminate
> possible causes of error. I took the same readings on my machine. I'm

I'm almost ready to buy separate controller, but all that I could find nearby
are based on the same Silicon Image chipset

> using an ASUS SK8N motherboard - that's the Promise TX2 SATA controller -
> with Western Digital's 36gb 10K RPM Raptor:
>
> /dev/sda:
> Timing buffer-cache reads: 128 MB in 0.12 seconds =1075.79 MB/sec
> Timing buffered disk reads: 64 MB in 1.20 seconds = 53.43 MB/sec
>
> I'm using the latest stable vanilla kernel (2.6.5), compiled today. It
> would also help to have your kernel config, if at all possible.

Sure. Attached is .config for 2.6.5-mm5
Thanks
--
/KoS
* If you can't say it in 50 characters, then don't b

Attachment: .config.gz
Description: GNU Zip compressed data