Graargh

[taimatsu]

My computer. It has free space on its hard disk. There is nothing obviously wrong with it. And yet it is grindingly, drearily slow, spending enormous amounts of time 'waiting for I/O' when I do more than the very bare minimum with it. This situation is new in the past month or so. I am running Debian Linux (etch) with KDE. How do I sort this out? I am sick of waiting minutes to open a KMenu item.

Comments

[james-r.livejournal.com]

New disk?

Is anything showing in /var/log/messages ?

[taimatsu]

Yes, there are many I/O errors. Really a lot. Here are the last two:

Mar 12 10:02:31 hikari kernel: hda: dma_intr: status=0x51 { DriveReady SeekCompl
ete Error }
Mar 12 10:02:31 hikari kernel: hda: dma_intr: error=0x40 { UncorrectableError },
LBAsect=2534921, sector=2534918
Mar 12 10:02:31 hikari kernel: ide: failed opcode was: unknown
Mar 12 10:02:31 hikari kernel: end_request: I/O error, dev hda, sector 2534918
Mar 12 10:02:36 hikari kernel: hda: dma_intr: status=0x51 { DriveReady SeekCompl
ete Error }
Mar 12 10:02:36 hikari kernel: hda: dma_intr: error=0x40 { UncorrectableError },
LBAsect=2534921, sector=2534918
Mar 12 10:02:36 hikari kernel: ide: failed opcode was: unknown
Mar 12 10:02:36 hikari kernel: end_request: I/O error, dev hda, sector 2534918

[crazyscot.livejournal.com]

Your hard drive appears to be dying and ought to be replaced. If you don't have an up-to-date backup of at least your personal files, DROP EVERYTHING AND MAKE ONE NOW.

[taimatsu]

Bollocks! Okay, at present I don't have a sensible backup. I could shove my personal files onto DVD, I imagine. I actually have a Mac Powerbook with free disk space which might work for storing things. r actually I have a second disk in the desktop machine, which is mostly full, but I could put things there.

Gah, I am so lacking in clue. Additionally, I can't drop everything, as essay deadlines loom lijke icebergs in my immediate future. Bleh. I might try to transfer my essay-work to the laptop, and then I could let the desktop chug away writing DVDs while I get on with stuff.

I'm curious - it looks like there is only one bad sector; does this *really* mean OMG bail out now?

[diffrentcolours]

Generally, if you're seeing one bad sector, it means you have many - the hard disk itself will attempt to patch and repair bad sectors using spare ones of its own, which slows it down. Once you start getting bad sectors, it's the beginning of the end. You're getting them for a reason, whether it's mechanical failure or old age, and they're not going to go away.

I advised you to make a backup some time ago, and also suggested that disk problems might be at the heart of your slowness, but we didn't chase this up.

[taimatsu]

Sure :) If you were me, how would you best do the backup? I will put essential stuff on DVD right away, but if I want to preserve other stuff, where would I put it?

[diffrentcolours]

If I were you, I'd take the hard drive up to Manchester this weekend and we can look at it (and buy a replacement) then.

[taimatsu]

Okay! I had better check my bank balance :)

[diffrentcolours]

Disk space is fivemack... MicroDirect's product list shows an 80GB drive (which is IIRC bigger than the one you currently have) for just 25 quid inc. VAT.

[oneplusme.livejournal.com]

I have a spare 250GB drive which is intended for taimatsu whenever she'd like to have it. That should save on costs...

[bateleur.livejournal.com]

does this *really* mean OMG bail out now?

In my experience: yes.

Modern disks are designed to be highly resistant to failures of any kind. At the point at which you start seeing clear signs of trouble that tends to mean the trouble in question is very bad.

[ewx.livejournal.com]

Received wisdom is that drives can hide the first N bad sectors and when the errors start becoming visible (as above) it's time to replace before it gets worse.

[crazyscot.livejournal.com]

I'd be leery of trying to burn a DVD when there's trouble on the IDE bus[*] - the burn process can be awfully sensitive. It would be safer to transfer things via network (if you have that set up, of course) or memory stick, or to the second drive. If you have sufficient files that a DVD is the only sane way to do the whole job, get the most important ones off by other routes first.

As others have said, bad sector problems tend to only get worse, not better.

If time were no issue a sensible recovery plan might be "remove disks; fit new disk; install fresh etch; add old disks; copy stuff off them; remove and destroy dying old disk". As things stand, I'd suggest it'd be safest to use hikari as little as humanly possible until you can find the time to sort it out.

[*] Light heartedly, I suppose you could say that the chugging and delays are because the data missed the IDE bus and had to wait for the next one ;-)

[diffrentcolours]

Doesn't everything these days have buffer underrun protection etc.? It's been a good few years since I cared about it when burning CDs and DVDs anyway...

[crazyscot.livejournal.com]

Maybe so; but that doesn't stop me from being paranoid. Say, have you seen my walking stick? :-)

[zandev.livejournal.com]

I second that.

What I do for emergency backups is copy crucial things to a USB thumb drive. You can get 4GB ones for 20 quid or so now, which should be enough to cover important documents.

[crazyscot.livejournal.com]

£5.13 + P&P (http://www.amazon.co.uk/Integral-COURIER-USB-Drive-Electronics/dp/B000KDT1CU/ref=pd_bbs_sr_4?ie=UTF8&s=electronics&qid=1205366889&sr=8-4)

[syllopsium.livejournal.com]

The issue isn't the number of bad sectors - it's where they are.

In my experience a small number of bad sectors will render important parts of your drive unreadable before the damage worsens. At that stage it's probably possible to retrieve the majority of your data, but it's more awkward as the disk may no longer be fully accessible and some vital data may be in the bad sector itself.

Do not do further work on the machine with a faulty disk apart from backing up - the more you use it, the more likely it will critically fail. Also, back up in strict order of decreasing importance.

The worst case scenario is that you get mechanical failure, the disk head crashes onto the platter and all your data is destroyed beyond hope of recovery other than by specialist firms. Switch the computer off and on as few times as possible (ideally : zero) before completing your backup.

On the bright side, bringing the disk up to Manchester shouldn't impact on its reliability. Modern disks are far more shock resistant than in prior years.

[thinkstoomuch.livejournal.com]

There's another possible explanation. Like everyone else, I've normally seen this from dying disks, and I completely agree; backup everything you want to keep, now.

However, I've also seen this because of a bad drive cable, which on a desktop is super easy to fix. There are ways to check but I am saying nothing until you've backed things up :P

You should probably mention the cable idea to Dave as it's one of those too obvious things that is easy to overlook. Certainly I dug around for hours before noticing "Hmm, this cable has a bit of a serious kink in it".

[danfossydan.livejournal.com]

*nods*
It could also be a problem with a controller card, or even a driver for that controller card.

On board controller card failure would be somewhat annoying.

[james-r.livejournal.com]

I've just realised this is your desktop machine rather than laptop - I've got a bunch of spare disks going free suitable for desktops which may be useful to you if you're interested. If so do you know if you need ATA or SATA, and how big is the existing disk?