Re: ahci slow transfer rate with kernel 2.6.23-2.6.25

Re: ahci slow transfer rate with kernel 2.6.23-2.6.25

[kyle]

Ok, I'll try set queue_depth to 1 to see if there's any improvement. btw, 
the same disk connected to sil3132 controller has no problem at all with 
queue_depth = 31, I got over 100MB/s for hdparm, dd, etc test with 
ST3500320AS + sil3132. So I assume the problem would be ahci.

Thanks a lot.

----- Original Message ----- 
From: Sergey A. Sukiyazov
To: kylewong@southa.com
Sent: Monday, April 28, 2008 5:11 PM
Subject: Re: ahci slow transfer rate with kernel 2.6.23-2.6.25


Hi

I have some problem. Try set queue_depth in "1" for disks, it disables NCQ 
and the transfer rate
has returned to 100MB/S. It's ST3500320AS problem with NCQ implementation (I 
think :-))

for i in sda sdb sdd sdf ; do
    echo "1" > /sys/block/${i}/device/queue_depth
done


See also: http://bugzilla.kernel.org/show_bug.cgi?id=8327

-- 
Best regards
Sergey A. Sukiyazov
http://corwin.rostovlinux.ru/