[copper_think]

Application Verifier is a feature of Windows for developers to use to check program correctness. Bruce says he turned on Full Page Heap, which makes every allocation go on a separate page, and tries to line it up so that the next page is not readable or writable. The idea is, if you go past the end of your memory allocation, the CPU raises a protection fault, and you catch the memory corruption bug at its source. Application Verifier can also do other things, like raise an error if your program ever passes an invalid HANDLE to a Windows system call.

Application Verifier is turned on by process name (i.e. "explorer.exe"). I think most of the time, developers turn on an Application Verifier feature, start just one process by that name, and then verify. But Bruce turned it on for a short-lived process that runs in a large build. So it runs thousands of times, and he hit this problem. It sounds like a great thing to fix, but I don't think it affects most developers using Application Verifier, and it definitely doesn't affect 'normal people' who are just using Windows on their laptop or desktop.

[brucedawson]

I do remember a coworker at another company complaining that their hard drive was filling up and it turned out the problem was the App Verifier log files. In that case the individual log files were enormous so a few dozen (hundred?) runs of the program under test was enough to be a problem. Different, but related, and perhaps more common than the problem which I hit.

[pletnes]

If the log files aren’t cleaned up, you’ll hit this issue even if you don’t run it 30k times in a minute. I ran into a very similar problem with pytest (python) creating sequentially numbered temp dir/files under /tmp on linux. Result: full / partition.