Why does winXP need to turn on the hard drive to copy text to clipboard?

Question

I was typing some text in notepad on my Eee PC with Windows XP on it, and at some point HDD stopped (it usually stops when there is no disk activity for some time). When I needed to ctrl-x a few words, the OS paused waiting for the disk (that sound of a starting HDD).

Why did it happen? Does text (or whatever) not go directly to RAM (even when it's just a couple of words)?

Answer 1

Windows, by default, uses processor and i/o idle time to eagerly write memory pages to the hard drive paging file. This allows memory to be more quickly swapped out in favor of other, more important memory when you do things like switch between programs or start a new program.

It's a scheme that was set up in the days before laptops and battery life considerations. Most of the time it's still a net win. If your drive were still spinning there'd be almost no downside, and it's hard to understate how much this helps performance. Sometimes (like when your drive has been spun down for a while) there might be battery-life advantages to waiting until the disk needs to spin up anyway, and writing as soon as it starts to be idle again. However, this would come at the cost of potential performance.

Answer 2

I assume, it loads the dll or binary that holds the function to push your text to clipboard.