Re: Slow disk - hdparm, S.M.A.R.T, badblocks, what else?
If this isn't a problem that suddenly manifested itself, it might be
the ide cable to the drive. I had a drive running slowly (a Maxtor,
too) and just got a big improvement in it's performance by using a new
cable. I got a round ATA133 cable for $4.00 and the drive's performance
radically improved. I knew it was the cable, though, because the drive
had been running fast in a nearly identical system with the only real
difference being the cable. Also, though you probably know more about
than I do, the -I flag of hdparm is pretty useful for info.
Richard
--- "Karsten M. Self" <kmself@ix.netcom.com> wrote:
> I'm trying to find out why my disk performance is so slow -- 150x
> worse
> than a comperable system -- and what I can do to improve it.
>
> I've got a system with a painfully slow disk. The worse as it's
> serving
> as a Samba server for a small domain (ten workstations). Saturated
> 802.1g WiFi is disk-starved presently. System response under any I/O
> load is glacial. 'top' routinely reports load averages of from 2 to
> 10+
> with 99% idle CPU. Memory utilization is generally nominal, and was
> *not* an issue in the tests below, though disk performance pretty
> much
> precisely sucked.
>
> Using hdparm, I'm getting disk reads at 128 kB/sec. A comperable
> drive
> on a similar system rates nearly 150 times faster[1], at 18 MiB/sec.
> I'd expect the slow drive to be capable of similar. 2.4.25 kernel on
> x86 HW. All reports following are with the system booted single-user
> and running minimal services.
>
>
> I *am* applying hdparm options including both DMA and UDMA (either
> mode
> 2 or 4, not entirely sure).
>
> Specifically:
>
> # hdparm /dev/hda
> /dev/hda:
>
> multcount = 16 (on)
> IO_support = 3 (32-bit w/sync)
> unmaskirq = 1 (on)
> using_dma = 1 (on)
> keepsettings = 0 (off)
> readonly = 0 (off)
> readahead = 8 (on)
> geometry = 4982/255/63, sectors = 80041248, start = 0
>
>
> The disk is a Maxtor 54098U8 40 GiB UMDA66 drive.
>
> It's S.M.A.R.T capable, and I've run some additional diagnostics
> using:
>
> - hdparm (-i -tT and no options)
> - smartctl (-L -S -X -a -c -g -i -L and -v options)
> - badblocks (no results when I left)
> - bonnie++ (a disk testing utility -- no results when I left)
> - Additional diagnostics: cpuinfo, dmesg, free, iostat, lsmod,
> lspci,
> and the /proc/ide/piix file.
>
> The results may be seen at:
>
> http://linuxmafia.com/~karsten/slow-drive/
>
> Comparative results for a fast system similarly configured (but
> different HW) is at
>
> http://linuxmafia.com/~karsten/slow-drive/fast-drive.tar.gz
>
>
> I installed the ide-smart and smartsuite packages, with which I'm
> pretty
> unfamiliar. One result which appears interesting, though I'm not
> sure
> it's significant, is the output of 'smartctl -v /dev/hda', which
> shows a
> large value in the Raw Read Error Rate attribute's Raw Value
> (smartctl
> -a /dev/hda):
>
>
> Vendor Specific SMART Attributes with Thresholds:
> Revision Number: 16
> Attribute Flag Value Worst Threshold Raw
> Value
> ( 1)Raw Read Error Rate 0x000a 253 252 000
> 343037
> ( 3)Spin Up Time 0x0027 182 179 063 27627
> ( 4)Start Stop Count 0x0032 253 253 000 1910
>
> The other drive has 0 rather than 343037.
>
> I see *no* CRC or other errors in /var/log/syslog or
> /var/log/kern.log.
> syslog is largely uninterrupted series of "MARK" entries.
>
>
>
> I do find a number of similar postings googling for 'hdparm kb/sec',
> many involving Maxtor drives of various models, but no clear
> resolutions.
>
> - Bad drive?
> - Bad configuration?
> - More data needed? If so, what?
> - Other?
>
> Assistance very much appreciated.
>
>
> Peace.
>
> --------------------
> Notes:
>
> 1. 149.36 times, if you're doing the math.
>
> --
> Karsten M. Self <kmself@ix.netcom.com>
> http://kmself.home.netcom.com/
> What Part of "Gestalt" don't you understand?
> Rules of Spam: #0: Spam is theft.
>
> ATTACHMENT part 2 application/pgp-signature name=signature.asc
__________________________________
Do you Yahoo!?
New and Improved Yahoo! Mail - 100MB free storage!
http://promotions.yahoo.com/new_mail
Reply to: