Lots of hard drive accesses with MacOS

Sorry, a post about MacOS again, but this is a problem my boss has been faced with, and judging by what google searches gave us as clues to go on, I thought it would be useful for others to know about this.

So here it is: for a couple of weeks, my boss's Mac had been slowing down very painfully, to the point that he was just sitting in front of it waiting for web pages to show up or applications to start... We tried a whole bunch of things, such as disabling spotlight, dropbox, and even the time machine, but nothing worked. Finally, he had a look at Disk Utility that said that the disk was gone beyond repair. Fortunately, a new colleague suggested to restore from the Time Machine, holding Command-R during startup. It took ages (over a slow network), but now the machine is up again, without any slowing down.