Subject: Re: large disk preformance (interactive lags in 1.5.1-BETA)
To: Laine Stump <lainestump@rcn.com>
From: Ken Wellsch <kwellsch@tampabay.rr.com>
List: current-users
Date: 04/09/2001 16:27:50
Laine Stump wrote:
> 
> Ken Wellsch <kwellsch@tampabay.rr.com> writes:
> 
> > What I've been seeing is that after a certain period of time, with something
> > like a tar unpacking a large tar.gz bundle (e.g. pkgsrc.tar.gz), that UBC
> > or someone, is merrily consuming *all* available memory and leading to
> > quiet processes getting swapped out. Thus after running something consumptive
> > like that for several minutes, getting response from your shell or some
> > other activity that hasn't been active for a while, is delayed until
> > it can get some resources back.
> 
> I used to get that, to the point that I was seriously considering
> backing down to 1.5. But then a few weeks ago the UBC stuff was given
> a tuneup in the form of setting maximums for certain types of memory
> usage, and now my system performs wonderfully - no more
> several-second-pauses when I switch to an emacs sessions while a long
> tar operation is running.
> 
> Are you completely up to date?

I rebuild my desktop about once a week.  Yes, I confess I have noticed
less of a drag on interactive things lately.

I suppose I am thinking lately more about dropping by every 30 minutes
or so while a "make build" is running, doing a "top" and noticing a
fair number of processes swapped out.

Admittedly these processes are not doing much, if anything, but it just
surprised me that things might get swapped like that.

I thought of UBC as using otherwise unused memory... but I guess over
enough time, something considers such processes swappable and does so.

The box is a PPro200 with 128Mb of memory.