Subject: Re: "parked" processes?
To: None <current-users@NetBSD.org>
From: Alan Barrett <email@example.com>
Date: 07/26/2007 11:57:19
On Thu, 26 Jul 2007, Andrew Doran wrote:
> > > I still encounter hands in which firefox is unresponsive, and most of
> > > its lwps are in "parked" state.
> Are you using any plugins with firefox?
Yes, a whole pile of them.
> Is there a way to reproduce the behaviour that anyone knows of?
It seems pretty random to me, but perhaps something like this would work:
* open lots of windows and tabs so firefox is using lots of memory
(I often have 30 to 60 tabs open, spread over 5 to 10 windows);
* stop touching firefox, but keep the machine otherwise busy for a
few hours, so that eventually firefox gets swapped out.
> > It appears that the problem is related to the process being
> > swapped out. Every time firefox is hung (unresponsive to mouse
> > clicks, doesn't even redraw the window when it is brought to the
> > foreground), I have found that "ps -l" reports that the process is
> > swapped out ("W" in the second character of the "STAT" column), and
> > that "ps -s" reports that every lwp is swapped out.
> Are these swapped out processes runnable (R)?
Never; it's usually "IWl" or "SWl".
> > Most lwps have WCHAN = "parked", but there's always one with "-",
> > and one with something else (usually "select" or "poll").
> That's how firefox usually looks. The "-" thread is likely a zombie
> waiting to be collected.
Even when everything is working normally, there's always one firefox
lwp with WCHAN = "-" and STATE = "ZW-" or "ZWL-". This seems odd.
(I am running NetBSD 4.99.23 on i386, but firefox-18.104.22.168 was compiled
under NetBSD 4.99.21.)
--apb (Alan Barrett)