Messages in this thread |  | | Date | Fri, 23 Aug 2002 12:01:52 +0100 | From | Athanasius <> | Subject | Re: 2.4.20-pre2-ac4 IDE is slow |
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On Thu, Aug 22, 2002 at 01:59:45PM -0400, Rob Speer wrote: > I'm going from 2.4.19 to 2.4.20-pre2-ac4 and the hard drive is noticably > slower in the new version. (It doesn't use DMA in either version - I > wish it did in ac4, but that's a separate problem.) > > What I seem to remember from the other message is that there's some > parameter that can be changed to bring the speed back up. Could someone > tell me what it is? > > > If it helps: output of hdparm /dev/hda > > /dev/hda: > multcount = 0 (off) > IO_support = 0 (default 16-bit)
This could be part of the problem too? I don't think I set anything specific to get to 32bit on my system. Hmmm, the multcount too? I'm starting to think, if this is your output from 2.4.20-pre2-ac4 that you're hitting a bug in the current code which is REALLY not doing the right thing for your controller.
> unmaskirq = 0 (off) ^^^^^^^^^^^^^^^^^^^^^^^
Try hdparm -u1 /dev/hda
> using_dma = 0 (off)
And may as well use -d1 too if it works on the device (yes, I know you said neither kernel enabled it per default). Then you're after finding which DMA mode the IDE bus and drive can do, 'man hdparm' for the possible values (like -X69 if it's all ATA100 capable for UDMA5). With a 60GB Maxtor and an 80pin cable I use:
/sbin/hdparm -u1 -d1 -X69 /dev/hda
root@emelia:~# hdparm -t -T /dev/hda
/dev/hda: Timing buffer-cache reads: 128 MB in 0.52 seconds =246.15 MB/sec Timing buffered disk reads: 64 MB in 2.03 seconds = 31.53 MB/sec
Although I'm wondering if with ATA100 and UDMA5 I should be seeing even better than that.
HTH,
-Ath -- - Athanasius = Athanasius(at)miggy.org.uk / http://www.clan-lovely.org/~athan/ Finger athan(at)fysh.org for PGP key "And it's me who is my enemy. Me who beats me up. Me who makes the monsters. Me who strips my confidence." Paula Cole - ME [unhandled content-type:application/pgp-signature] |  |