Subject: Re: jerky interactive behavior
To: None <current-users@NetBSD.org>
From: Steven M. Bellovin <email@example.com>
Date: 01/22/2007 09:56:46
On Sat, 20 Jan 2007 21:23:22 -0500
"Steven M. Bellovin" <firstname.lastname@example.org> wrote:
> I recently upgraded my kernel to one from January 8 (and then to one
> from today). Before that, I'd been running a mid-December -current.
> Interactive performance on my Thinkpad T42 has become completely
> unacceptable. Something else -- I have no idea what -- occasionally
> grabs the CPU. Moving the mouse shows jerky cursor motion, I get
> doubled input characters, etc. ps and top show that the machine is
> mostly idle, though xosview sometimes shows brief spurts of 100% busy.
> It isn't swapping (it's got 2G of RAM), the interrupt load doesn't
> seem high (about 1.4-1.6K/sec, with HZ set to 1000), etc.
> Is anyone else seeing this? Anything I should do to tune it? Might
> the new scheduler code be part of it?
Here's a possibly-interesting data point. I was using my laptop on
the train this morning, without trouble. As soon as I plugged in my
EVDO Cardbus card, I started seeing the hesitations and jerkiness in
mouse movements. When I was having trouble over the weekend, it was
while using a mini-PCI ath0. Might those be linked? (It's a bit odd to
think that I'd have trouble with those and not my GigE wm0...)
--Steve Bellovin, http://www.cs.columbia.edu/~smb