slow PATA disk in Centos

[bruce56]

While building some workstations with Centos operating system,
I found some Deskstar 320 GB PATA disks that were hardly used (about 30 hours).
I used these for swap and tmp, although swap shouldn't be used, as there is
heaps of RAM. I used SATA disks for root and home.
Now I find this Deskstar is very slow on one workstation.
Benchmark gives 4 MB/s read, when it should do about 100.
The Deskstar disk is 7200 RPM and supports UDMA6. The mainboard uses a Jmicron
chip for PATA, which also supports UDMA6. It is connected with
80-conductors cable. I swapped the Deskstar drive and the cable, and slowness
seems to be in the mainboard.
RHEL generic IDE driver is claimed to support the JMB368 since version 4.6,
and I have version 5.10.
hdparm shows the drive is running in UDMA5, which is ATA100 instead of
maximum ATA133, but is way faster than 4 MB/s
The SMART data shows no problems with the drives.

 

[Paul]

While building some workstations with Centos operating system,
I found some Deskstar 320 GB PATA disks that were hardly used (about 30 hours).
I used these for swap and tmp, although swap shouldn't be used, as there is
heaps of RAM. I used SATA disks for root and home.
Now I find this Deskstar is very slow on one workstation.
Benchmark gives 4 MB/s read, when it should do about 100.
The Deskstar disk is 7200 RPM and supports UDMA6. The mainboard uses a Jmicron
chip for PATA, which also supports UDMA6. It is connected with
80-conductors cable. I swapped the Deskstar drive and the cable, and slowness
seems to be in the mainboard.
RHEL generic IDE driver is claimed to support the JMB368 since version 4.6,
and I have version 5.10.
hdparm shows the drive is running in UDMA5, which is ATA100 instead of
maximum ATA133, but is way faster than 4 MB/s
The SMART data shows no problems with the drives.

It does sound to me like PIO mode (4 to 7MB/sec), so you're
looking in the right area. You would think of
all utilities, hdparm would know what it was talking
about.

If there is a dmesg, see what happens to the drive when it
is detected, and whether any anomalies are noted.


Paul

 

[bruce56]

It does sound to me like PIO mode (4 to 7MB/sec), so you're
looking in the right area. You would think of
all utilities, hdparm would know what it was talking
about.

If there is a dmesg, see what happens to the drive when it
is detected, and whether any anomalies are noted.

I know that when Win2000/XP counted disk errors, they ratcheted the speed
down until you ended up with PIO. I don't know if linux kernels do the same.
I'll put it down to a flaky interface, and use a SATA disk instead to get
it going.

 

[Mike Tomlinson]

hdparm shows the drive is running in UDMA5, which is ATA100 instead of
maximum ATA133, but is way faster than 4 MB/s
The SMART data shows no problems with the drives.

Replace the cable, make sure the drive is set to cable select and is on
the end of the cable.

Post the results of 3 runs of "hdparm -Tt /dev/hdX" where X refers to
your Deskstar drive.

 

[Flasherly]

While building some workstations with Centos operating system,
I found some Deskstar 320 GB PATA disks that were hardly used (about 30 hours).
I used these for swap and tmp, although swap shouldn't be used, as there is
heaps of RAM. I used SATA disks for root and home.
Now I find this Deskstar is very slow on one workstation.
Benchmark gives 4 MB/s read, when it should do about 100.
The Deskstar disk is 7200 RPM and supports UDMA6. The mainboard uses a Jmicron
chip for PATA, which also supports UDMA6. It is connected with
80-conductors cable. I swapped the Deskstar drive and the cable, and slowness
seems to be in the mainboard.
RHEL generic IDE driver is claimed to support the JMB368 since version 4.6,
and I have version 5.10.
hdparm shows the drive is running in UDMA5, which is ATA100 instead of
maximum ATA133, but is way faster than 4 MB/s
The SMART data shows no problems with the drives.

quite a few ideas to pursue for resetting UDMA in the Wenviron, a
few(er) hardware centric
http://winhlp.com/node/10