As some may be aware, certain memory operations cause the session private memory pool to explode in usage in win10. This bug was actually introduced in win8, causing many programs that previously did not have leaks to indirectly leak memory as windows keeps
expanding the session private pool when they're running and never freeing that memory up even after the programs are closed. Older versions of windows (confirmed 7 & Vista) do not exhibit session private expanding at all under these circumstances. Only ending
the session via logging out causes it to be freed again.
This memory usage can normally not be seen in task manager, since session private is hidden from users even while it contributes to the amount and % currently listed as "in use". However, using rammap the growth of session private is clearly visible.
I've tried getting in contact with MS before to report this, but haven't ever had any luck finding someone in the core OS team who could reasonably evaluate it even though it is major concern for anyone who uses persistent sessions (the session private pool
growth is frequently in excess of 200MB/hour when running affected software).
Is anyone at MS looking at this issue? Has there been any progress on it? It is absurdly easy to reproduce; just run the affected software and rammap at the same time, and watch the session private pool grow to devour all ram.
Affected Software that I (personally) know of:
- Any games made with gamemaker studio
- Any games made with RPGmaker VX or VX Ace
- Adobe Premiere Pro
- X-plane
I suspect that this issue may be enormously under-reported due to the fact that it is effectively invisible to users who don't run rammap, and may affect a very large number of legacy win32 programs.
If someone from MS who is actually capable of taking at look at this is curious, a Path of Exile developer wrote about working around it. While his example may not be the only function causing this issue, it definitely is a good starting point.
If anyone has additional information about this leak, I'd love to hear about it. Even better if they can help get information about it to someone at MS who can fix it.