On Windows, the Resource Monitor will let you watch most filesystem activity, filtered by process.

Some types of I/O show up as being by the 'System' (pid 4) process as well.

The best way is Sysinternals Procmon, as it literally lists every registry and file I/O call.

If my car engine started running in the middle of the night in my garage when I expect the car to be off, naturally I'd assume it was a plot hatched by automakers in conjunction with gas suppliers in order to increase profits on gas consumption, either that or a plot to kill me with carbon monoxide poisoning while I sleep... Call me a cynic I guess.

If Chrome in task manager shows a lot of disk usage when nothing is being done in the browser I'd naturally think the worst of them. Call me cynical, but hey, there are countless stories of Google not exactly behaving itself as a company.

> by running a filesystem or system call trace on Chrome processes

how do you do this?

I gave some pointers in the next paragraph.