On May 11, 2012 5:16 PM, "Jason Evans" <<a href="mailto:jasone@canonware.com">jasone@canonware.com</a>> wrote: > > On May 10, 2012, at 11:55 AM, Justin Lebar wrote: > >>> In summary, I don't think there's a problem here to fix. Am I missing > >>> something? > >> > >> We could use RSS - number of madvised pages, for sure, but that doesn't > >> quite help with people looking at their task manager ans seeing memory > >> usage 1GB higher than what it actually is. (And it doesn't help to make > >> the numbers Firefox itself reports believable) > > > > Yeah, the perception problem ("I looked at the task manager and > > Firefox sux!") is a real one that, from MemShrink's perspective, we > > need to solve. > > It's unfortunate that the operating systems don't expose statistics that provide clarity here. I don't want to make aggressive purging default behavior, To be clear, what we do at moment is purge only right before we query the OS for our RSS. In practice, this happens whenever we load about:memory or run a telemetry ping, which happens every few (five?) minutes when the browser is idle. Its not ideal from the standpoint of a user looking at the task manager, but at least our stats are correct. I think we'd want the same behavior, purging only upon a malctl, rather than automatically.