As you run Firefox, it leaks memory. This is well known by now, I am sure, and it should go away by closing and reopening it right, because a process's memory is freed on closing, right? That's what I thought, but Process Explorer, and my computer's pop-ups saying "Close programs to prevent information loss", disagree with me. Notice the System Commit in the following two screenshots below (my understanding is that this is equivalent to amount of space consumed on the allocated page file) - it is far higher than the combined sum of all memory usage by all processes Process Explorer shows, even after closing and re-opening Firefox:
When I close and re-open Firefox, instead of all of the System Commit leak it has produced being removed, it only removes the amount of memory it has at that point in time - up to about 3 gigabytes at worst, but it can leak 30+ gigabytes of System Commit. In this case I only get back about 0.9GB, barely enough to run Firefox again:
Since Firefox leaks more System Commit than it has memory at any point in time, this eventually leads to a state of being unable to run anything new until I restart my computer, which fixes the problem.
I have tried increasing the page file, no good - Firefox just consumes however extra amount of System Commit I let it have! (And you could just say, 'Swap to another browser' - but what if that browser also has a System Commit leak, or what if I experience it with a different program entirely for which there is no alternative? So I am looking for a general solution.)
What steps can I take to restore System Commit to normal levels, without restarting my computer? (I do not need Firefox's memory leak itself to be fixed - I am fine with having to restart it every now and again, because it does so very promptly, so this is distinct from asking about fixing Firefox itself.)