Very low writing speeds on RAID 0 with HPT374

I am experiencing a very strange problem with extremely
low writing speeds, and I'd be really glad if anyone had
a solution for it:
As I noticed a significant decrease in system performance,
rendering video capture (which never was a problem before)
virtually impossible, I did some benchmarks and found a
ridiculous low writing speed.
To exclude software problems, I did a clean new install;
the following results were collected with only

- WinXP, SP2 & MS security updates
- Latest VIA Hyperion
- Latest ATI Catalyst
- HPT374 Driver 1.21.0.0 (10.03.2002)
*No other software installed*

System configuration:

AthlonXP 2600+
ATI Radeon 9700Pro
1 GB DDR333 RAM
Epox 8K9A3+ with HPT374
Latest Award Bios (13. Aug. 2004)
HPT374 Bios 1.24

4 Seagate ST3120026A (120GB/7200rpm/2MB), connected separately
to the 4 controller channels, configuered into 2 Stripesets
(Raid 0), 240 GB each, each partitioned evenly into 2 x 120GB.

"Performance Test 5.0" from PassMark gave me:

Sequential read 63,8 MB/s
Sequential write 2,8 MB/s *no typo!!*
Random seek + RW 3,9 MB/s *no typo!!*

Testing practically by copying a 4 GB file between both arrays,
in every direction (array1 -> array2 and array2 -> array1) I get
calculated speeds between 9 and 11 MB/s, what, as reading performance
seems ok must be limited by writing speed.

I did try to update the Windows driver for the HPT374, what resulted
in the controller beeing no longer recognized by the Highpoint
RAID-Management software, so, although controller & driver were
displayed correctly in the device manager I turned back to the 1.21
driver - performance was unchanged anyway.

Grateful for any ideas,

Schorsch

What happend to the system just before this occured?

I suspect that the system was running great and then something happened one day.

You may be dealing with a BIOS setting issue or a HDD malfunction.

Have you tried borrowing another RAID controller and testing the drives on that controller? Have you tried backing up your data on the drives and rebuilding them from scratch in the RAID BIOS?

Let us know.

Foxy

You're right, the system was great before this began. It's about one month now, and I can't remember anything special happening.
A HDD malfunction seems not very likely to me, as I never had data loss or reading problems, and I can't imagine a malfunction that is absolutely limited to writing (internal cache problem? maybe... but in both arrays simultaneously?).
I'll try rebuilding one of the arrays from scratch and test again.

Schorsch

I did rebuild one array from scatch, now with a stripe size of 16k (as this array contains OS & programs with lots of small files), same results.

When restoring the partitions on the newly built array (using Powerquest Drive Image), I noticed, that a partition with 7065 MB of data was restored in 3:37 min., giving me a write speed of 32,5 MB/s if I assume that the partition data is written as a continoos stream; as this is not quite what I expected but still the 7-fold value as under windows, I'm not sure if I have a hardware or software problem.

Schorsch

HPT374 Driver 1.21.0.0 (10.03.2002)
HPT374 Bios 1.24

Click to expand...

When working with RAID0, specially with HPTech, make sure to have the same BIOS & Driver revision. Using imaging software to recover from a failed array of just simply doing a shortcut & not reinstalling often causes problems, a clean install with the matching drivers is recomended.

Boot into the recovery console and run "chkdsk /r" to check that you don't have file or sector problems slowing things down. Sounds to me like you file system is having problems verifying writes or being allocated space. If you have lots of bad sectors or improperly mapped sectors things can really slow down. I think chkdsk will find these and get rid of them.