Hmm, I'm no expert. But AFAIK open memory mapped files are counted towards a process's virtual memory (as displayed by utils like 'top' and 'ps). Dunno if FF us

Hmm, I'm no expert. But AFAIK open memory mapped files are counted towards a process's virtual memory (as displayed by utils like 'top' and 'ps). Dunno if FF uses memory mapped files extensively. There's a utility called 'pmap' that you can use to display the memory mapped files and subtract it from the total etc. Finding out how much memory a program is using is surprisingly tricky to compute. Good luck.