Konstantin Svist wrote:
Hi all,
I'm investigating slowness on my old laptop (HP ze4400, circa 2004;
see related thread "hdparm shows poor performance on cached reads for
PATA drive" if you're interested).
Apparently the HD cached read speed is not the only thing that
suffered a performance hit.
I ran nbench (http://www.tux.org/~mayer/linux/bmark.html) on the
laptop and got the results that showed that the performance is roughly
half of my newer laptop (Dell E1505) - which was very surprising,
since the new laptop is not THAT much more powerful than the old one
(plus, I'm pretty sure the test didn't use both cpu cores on the new
one).
I decided to try nbench in knoppix environment - and to my surprise,
it performed nearly as well as (and in a few tests, better than) the
new laptop!!
I've ran the same test on the new laptop in knoppix - and found that
the results weren't affected all that much.
I've also tried nbench on the old laptop in runlevels 3 and 1: 3 gives
same performance as 5, but 1 gets somewhere in the middle between
knoppix and F8/runlevel 5.
What should I investigate next, to find the cause?
What do the results so far suggest? I'm guessing some part of the
problem is the services that start up in init 3/5 - and perhaps the
new kernel can be partially blamed, as well
Has anyone else experienced a problem like this? What can be done
about it?
Answering my own question
After some more digging: apparently the resource hog was wdaemon (daemon
that emulates a drawing tablet so that it can be hotplugged into X).
This was a surprise since my new laptop also has the same one installed
- and doesn't exhibit the slowdown.
I've emailed the maintainer and asked him to check out the problem.
Another service that affected the speed was cpuspeed - but that's only
when "performance" was not selected as the current profile.
P.S. Apparently this was the same issue as the HD performance indicated
by hdparm - who knew :)
