Subject: Re: mips UVM -- Re: mindless boredom, speed and compiling kernels
To: None <port-pmax@NetBSD.ORG>
From: Michael L. Hitch <mhitch@lightning.oscs.montana.edu>
List: port-pmax
Date: 05/19/1998 21:28:06
On May 19,  7:21pm, Jason Thorpe wrote:
> On Wed, 20 May 1998 09:30:32 +0900 (JST) 
>  nisimura@is.aist-nara.ac.jp (Toru Nishimura) wrote:
> 
>  > >>   UVM stable?  How about when it even runs?  [I can boot it, but as soon
>  > >> as it runs out of free memory and the page daemon starts to run, it hangs.
>  > >> The page daemon seems to hang trying to do I/O.]
>  > 
>  > Um, I've heard differently.  I'll talk with the guy who's making a
>  > progress with his machine.
> 
> Now that the pmap bug that kept it from running at all is fixed (nice
> hunting Tsubai and Michael!), I am planning on running it on my DECstations
> to see how well it works...  I'm just really surprised that it's that
> unstable on the MIPS.
> 
> Perhaps the reason it "hangs" when the pagedaemon becomes active is because
> the MIPS pmap doesn't do referenced/modified tracking?  (Although, if that
> were the case, it would certainly be unfortunate if UVM couldn't cope with
> that...)

  What I am seeing is that pagedaemon wakes up, scans one page, and then
waits in "getblk".  I haven't had time to track it any farther.  I've
looked at the UVM changes in pmap a bit, but couldn't see anything obviously
wrong.

-- 
Michael L. Hitch			mhitch@montana.edu
Computer Consultant
Information Technology Center
Montana State University	Bozeman, MT	USA