Recently I’ve been having a difficult performance issue on my primary Windows PC. Basically it’s involved sporadic system hangs with lots of disk activity that didn’t seem related to a specific application. The HD activity light would come on for 5-15 seconds, hanging the machine. Then it would recover and all would be well for a random amount of time.

I put the system through all the usual checks — spyware, viruses, and so forth. Nothing showed up (as it should not, since the machine is pretty heavily protected). I tried shutting down various services and applications, like the firewall and various System Tray applications. No effect. Next, I updated video drivers and made sure there were no known issues involving compatibility or Windows updates that occurred recently. The problem persisted.

Finally it occurred to me that I was over-thinking the problem, and that it might lie at a much lower level. So I opened Event Viewer, cleared all the logs, worked for a while, then opened the System log and took a look. The problem was immediately visible — a disk is going bad. The Log is showing multiple cases of bad blocks on HardDisk0, which is the system drive. That’s not good, and it definitely explains everything. Now the problem is to get a new disk, open the box, hook up the new drive temporarily while the old one is still in place, and use Partition Magic to clone the partitions onto the failing drive.

Of course, I need to do all this before the existing disk decides it’s time to go to the Great Silicon Graveyard. In the meantime, I’m trying to pull a backup from both partitions on the failing drive, just in case it fails completely before the replacement shows up in the mail.

The lesson is clear: you can’t blame all performance problems on spyware or disk fragmentation. Sometimes the problem is much more fundamental. If you’re having a problem like this, check the basics. Make sure no errors are showing up in the system logs, or in another hardware-related location. The data you save may be your own.

This entry was posted on Monday, June 22nd, 2009 at 8:40 pm and is filed under Disaster Recovery, Troubleshooting. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.