Subject: Re: UBC performance/tuning "issues"
To: Wojciech Puchar <wojtek@chylonia.3miasto.net>
From: Greg A. Woods <woods@weird.com>
List: port-i386
Date: 06/19/2002 16:51:56
[[ note redirect to tech-perform ]

[ On Wednesday, June 19, 2002 at 21:56:01 (+0200), Wojciech Puchar wrote: ]
> Subject: Re: NetBSD 1.6 Release Schedule
>
> > > i hope UBC will be really fixed. present behavior is inacceptable.
> >
> > UBC seems to be working fine. What do you think is wrong with it? Or
> 
> not only think but see and already did send-pr.
> 
> on heavy disk usage whole machine slows down incredibly and there are 5-10
> seconds reaction in X programs. using navigator etc. is almost impossible.

That's because, I believe, you have not yet properly tuned your system
(i.e. your kernel and perhaps also some of the "tunable" resources) for
your most common application mix.

> it NEVER happened in 1.5.2!

That's because 1.5.2 doesn't have UBC and can't be mis-tuned.  It always
behaves "badly" for everything and every type of use.  ;-)

> > is this your claim that the max/min memory usage sysctls aren't working?
> 
> yes it is. try vm.filemin=1 and vm.filemax=2 and then copy something
> large.
> 
> even if most of memory is used by apps they will be swapped and file usage
> exceeds 20% !!!

I have noticed that the latest release of Mozilla (i.e. 1.0) comes to
life far more slowly after long periods of inactivity, even under the
very same kernel and on the same unchanged hardware, than earlier
versions did.  Are you sure this isn't all you're seeing -- i.e. some
change in the patterns of memory use in the applications you're using?

-- 
								Greg A. Woods

+1 416 218-0098;  <gwoods@acm.org>;  <g.a.woods@ieee.org>;  <woods@robohack.ca>
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