Subject: Re: i386 1.4Q hangs nonrandomly?
To: maximum entropy <entropy@zippy.bernstein.com>
From: Ethan Solomita <ethan@geocast.com>
List: current-users
Date: 01/27/2000 13:16:50
maximum entropy wrote:
> 
> >softdeps is known to be pretty evil with memory management (Frank and
> >I have some ideas on how to fix it, but there's a decent bit of work
> >involved).  These other applications that you ran could certainly put
> >a strain on your KVA space, as well...
> 
> OK, that sounds like a perfectly reasonable explanation.  Especially
> in combination with the "livelock" softdeps bug being discussed in
> another thread, all this is starting to make a little bit more sense
> :-)
> 
	Soft Updates is particularly susceptible to eating memory during a
large series of removes, but that has always led to panics for me, not
lockups. In particular, the kmem_map runs out of virtual address space.
This has been improved greatly with Kirk McKusick's latest changes. In
my testing, it requires three different processes to be doing huge file
removals in parallel before it'll eat an unbounded amount of memory.
This is still a bug, but it's much more tolerable for most people.
	-- Ethan