process_utilization_stats failed with NOT_FOUND error, Ubuntu 22.04 about nvml-wrapper

[Baughn]

Some observations:

• The problem persists between restarts of the NVML-using program.
• If there is only a single compute process running, and I restart it, then the problem temporarily disappears.
• Passing in a timestamp makes it far more likely to break. If I always pass in None, then it'll usually keep working for half a minute or so, polling every 2s.
• nvtop doesn't have the issue. What do they do differently?
• Feels like a driver bug. Does this happen on every GPU?

[Baughn]

Here's the relevant nvtop code. Looks pretty different: https://github.com/Syllo/nvtop/blob/0316ce19581c3d8543cf6aa312d1569c56ca754f/src/extract_gpuinfo_nvidia.c#L761

[Baughn]

Another observation: Processes appear to only be returned if they are running. An idle process doesn't end up in the array, unless it was non-idle very recently. This accounts for what happens if I set the timestamp -- it reduces the horizon.

Also means that swallowing the error (and returning []) should be a valid workaround.