> 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

hi,

yesterday i ran into similar thoughts:

i'm setting up a Sun Ultra 10 and made it run under heavy load to test 
it's reliability under NetBSD ('sleep forever' seems solved, but i'm 
suspicious ;).

because i already had four shells open on the machine i was working 
from on the U10, i ping'ed the U10 in one shell constantly.

surprise (unfortunately i don't have the numbers, may repeat it on 
demand): although nearly every ping was replied to within 0.6 to 0.7 ms 
(it's connected to a hub/repeater), a few ones took 5ms or even longer.

i think that's not related to my network, i could test this on a fully 
switched (on a managed switch) segment to exclude this.

concluding: i think even the IP stack suffers from the phenomenon you 
described.

cheers,

-- 
Timo Schoeler | http://macfinity.net/~tis | timo.schoeler@macfinity.net
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