Strange hard drive problems.

Factual Questions
1

I’ve had 2 IBM 30 gig drives in raid 0 functioning fine for a while. I recently installed an 80 gig WD special edition caviar drive on another controller - the raid disks are on my onboard raid controller, and the WD is on the integral motherboard controller.

Anyway, I wanted to copy a whole bunch of data from the raid array to the WD. I partitioned the WD with partition magic 7 into one primary 30 gig partition and an extended 45 gig partition. An unexplained message popped up during the formatting (this is possibly the cause of it all), but hitting ‘apply’ again seemed to work. Anyway…

I start copying stuff. It FLIES. I had a practical transfer rate of about 60 MB/s. After about 10 gigs of copied files, I started to get weird problems. The transfers would drastically slow down, and seem to ‘pulse’, that is, stop and go, stop and go - and my computer acted extremely slowly (as if a high priority thread was taking 99.5% of my cpu) - things opened slowly, the mouse movement was jerky, etc.

I ran HDTach at that point and it confirmed that my drive was slow as hell - 3mb burst read, and 2.5-3mb/s transfers. HDtach earlier gave me 35+ meg reads, etc. So something has happened that caused the drive to go really slow.

So I rebooted. That fixed the problem for a little while. But after a lot of copies, it’d start bogging down again. I checked for memory leaks, and memory usage was pretty constant. Well, I was trying to figure that out when…

I had about 25 gig on the second partition. 20 was left open. And I tried to copy stuff to the drive, and it would give me a “this disk is out of space” error. Tried copying other things, same problem. Confirmed in a command prompt window and windows explorer that the partition has 20 meg free.

Well, if the partitioning process got screwed up, and the partition IS somehow at the end and is full, that might explain the slower writes - except that they happened also earlier when it wasn’t full - and it wouldn’t affect the hdtach test, which is strictly a read test.

It makes no sense to me. Why would it start slowing down after a lot of transferred data? And it’s not (assumably) a windows problem if the relatively low level HDtach also reports the drive has slowly down by an order of 10.

Anyway, this is very odd behavior, and I’m at a loss to explain it. Next plan, I guess, is to wipe the current partition structure (if there’s an error) and use win2k or fdisk to create a new partition structure and start again. But it doesn’t really explain the slowness, even if it is a partition problem of some sort.

Anyone have any idea whatsoever what’s going on?

2

Quick reminder: do not use RAID mode 0. If one HDD goes down you are goind to lose everything.

3

What OS do you use?

4

Win2k. And I understand the risks and benefits to raid 0, and it works best for me anyway.
I have thorough backups and the benefit in speed is worth it.

5

Don’t feel bad. I use RAID 0 and love the speed benefits. Got critical stuff (not much) backed up on CD. The really crappy thing is if one HD goes out you need to find an identical (or nearly so) drive to replace it with. Upgrading the RAID to something larger effectively means replacing all the drives at once.

On to your OP: I had this problem when copying large files from the RAID to a second drive. Turns out it must have been an IRQ confict of some kind. Monkeying around in the BIOS trying various things eventually made everything fly, but it never did the “partition full when it’s not” thing. That sounds more like your partitioning didn’t go well (and you said you got a mysterious message). What file system are you using, NTFS or FAT16/FAT32? I’d say wipe, repartition, and try again. If it still happens, return the drive.

6

I see that there’s no speed benefit to RAID 0, particularly when you are using ATA devices. YMMV.

Try re-partition the HDD.

7

Sequential transfer rate sees the largest benefit, and speed is almost doubled. Seek-time dependent applications obviously don’t see a lot of benefit. My RAID array most certainly has a benefit in some areas.

Anyway, I’ll try repartitioning it.