Dear list members,

I regulary use one of several different NetBSD2.0/i386 desktop
machines, and have sometimes noticed an intermittent "non-
responsivenes", which has started to anoy me. Sometimes my
mouse will "just stop moving", sometimes things will become
"sluggish" for several seconds. This does even happen when no
swap is being used, so a general "lack of memory" does not seem
to be the issue.

The machines cover a range of hardware, from a 1.4 GHz P4 with 256
MB ram, to AMD64's with 1.5 GB ram at 2GHZ. All of these machines
have local harddisks for swap and root, some use local /usr and
/home, others use NFS mounted volumes. In all these machines are
fairly well equiped to run X, mozilla, nedit, openoffice and the
like, so I expect that more people are seeing similar issues,
and either have chosen to ignore this (as I did so far), or have
tuned their system to get better interactive responsiveness.

Are there any general tuning guidelines, perhaps a FAQ or manual?

Are the default settings reasonable defaults for any machine role
(NFS-server, database-server, desktop-machine etcetera), or are
they just a smallest denominator?

Though it may be unrelated to the "non-responsiveness" issue,
a little test program writing 8192 files of 1MB each reveals
that there is a certain "spikiness" in the timing of writing each
1MB file. In particular at ~30 second intervals, it can suddenly
take >2 seconds to write a file instead of the (more usual)
< 0.1 seconds. What could this be, and can this be avoided by
proper tuning?

I have fiddled a bit with some sysctl parameters, but have so
far not been able to come up with anything very usefull; perhaps
because I'm looking in the wrong direction?

with kind regards,

Theo Borm