current_commit stat negative

[maxbachmann]

I am currently porting mimalloc to a new platform. When running it with my application I do get negative values for current_commit from mi_process_info after some time. It's a debug build so MI_STAT is set to 2. My port doesn't provide an implementation of _mi_prim_process_info so this is completely based on mimallocs own tracking.
I am working off of the latest tagged version v2.1.7.

Is this expected? If not is there anything known that could cause this and that I could look into?

[daanx]

That looks like spam? -- I would not click on that link. Let me see if I can remove it..
(as an aside, I think the commit can be negative due to thread interaction but let me think about this a bit more and reply in more detail)

[maxbachmann]

From my understanding current_commit should match the amount of memory committed in prim.c. If I add my own atomic to track the calls in there the numbers match for a while and start to go out of sync once threads get destroyed.

These two numbers match for a while and then appear to go out of sync once threads start to get destroyed. At this point current_commit appears to get decreased by 32mb without any corresponding decommit in prim.c.