I am watching my CPU load with gkrellm, and every 10 seconds it spikes to around 40% even if I am doing nothing. For some reason, this causes a problem when I am typing. Whatever character I typed when the spike occurred gets doubled. I endd up with sentences like thhis. How can I find out what is going on and stop it?

I'm using KDE under Mandrake 10.0. (Just installed a week ago. Moved from Red Hat.)
It doesn't seem to matter what program I am typing in.
I tried turing off crond, but that didn't do anything.
KDE System Guard shows that X is the program hogging the CPU every ten seconds, but I obviously can't kill that.
Once in a while everything works fine, but I can't figure out what's different then.
I'm not a total newbie, but I'm out of ideas.

---Dan

With my computer when you're doing nothing it doesn't go higher than 1%. Thing might also run smoother if you install the original drivers for you're graphic card (NVIDIA, ATI,...). Also check you're Mandrake updates to see if you have the latest XFREE68 installed

You could run top for a bit and see what program is causing the CPU spike

System Guard does the same thing as top, it's just prettier. Both show X as the program that is causing the spike. What do I do about THAT?
(I had to backspace over a double letter three times while writing this post. This is getting intolerable.)

---Dan

Wow. I'll be upfront and say that I don't have a clue why X would spike to 40% cpu usage, but it might be worth looking in the X log as well as the system and messages file and see if X is complaining about anything. I suppose that it's possible that X is having trouble with your video driver, but that is just a WAG. When you configured your system, did you have a choice of drivers to use? If so, it might be worth trying a different one.

Maybe you are routing your Font server over Bejing

I checked the messages and system logs as well as several others and didn't see anything enlightening. I didn't know that X had its own log though. What is it called, and where is it? I didn't see anything that sounded like it would be for X in the /var/log directory.

This whole thing wouldn't bother me if it weren't for those random double letters.

Thanks,
---Dan

I'm not sure about RH, but Slackware keeps it in /var/log. It is helpfully named Xorg.0.log. However, RH9 is probably using XFree so I think the name would be XFree86.log (or something along those lines)

I suppose as a last resort you could rip out the X rpms and re-install X from CD.

Ok. That helped. I read the log file, but there was nothing in there. It was pretty short, and there were no errors, complaints, or gripes. Reinstalling hardly seems necessary because I just installed Mandrake about a week ago. Whatever it is must have come with Mandrake because all I've installed that didn't come on the disks are a CD ripper and an MP3 encoder front end, neither of which is running. Having to reinstall Windows twice a year was part of what made me switch to Linux in the first place. Hasn't anyone else ever had a problem like this?

---Dan

Well, I wasn't talking about re-installing Mandrake, I was suggesting re-installing just X. However, before you take a step like that, have you investigated using a different driver for your video card?

If you really have to reinstall everything again, I would suggest you a different distro than Mandrake. It just sucks (IMHO). I had a REAL pain in the butt with Mandrake and I've seen too many users having troubles as well. I switched to RH and later on to FC2 and now all is smoothy.

But, as Hangdog42 said, first of all make sure it's the only solution left. Check video drivers or some background programs that may have some conflict with X.

The video card driver is correct. But...
I have discovered something new and interesting! First, it's KDE. I tried switching to the Gnome desktop, and I didn't have any problems. I like KDE much better (except for this problem).
Second, some programs cause this problem, and others don't. Here are some I've tested specifically, and whether or not they cause the CPU spike/double letters:

showimg (KDE-based file viewer): NO
the GIMP: NO
gkrellm (system monitor): NO (it's always on)
Quanta + (html editor): YES
KWrite: YES
Galeon (GNOME-based web browser): YES
Konquerer: YES
Mozilla: YES

What's more, if the programs are minimized, they don't cause the problem then either. However, if they are maximized, covering them up by a well-behaved program doesn't fix it.

That might be enough info for someone to take a guess as to what component is causing the problem. I just hope people are still reading this thread. Would it be bad manners to start a new one with everything I now know?

---Dan

That's pretty interesting, unfortunately I sure don't have any suggestions. If it is any consolation, a little googling shows that you are not the only one having this problem with KDE, but I didn't see any suggestions other than to use a VESA driver instead of a card-specific driver.

I'd give this thread a little longer (maybe a bump or two) and if you don't get any answers, re-post as a KDE problem.

Using a VESA driver does indeed make the problem almost go away. I still get a little spike, but don't seem to have any problem when typing. I only get one choice in refresh rates though, and it's an instant-headache-inducing 60Hz. Maybe I will just use Gnome for a while.

I will look around and probably re-post as a KDE problem. Thank you to everyone who responded!

---Dan

You might want to take the opportunity to check out some other environments besides Gnome and KDE. Xfce seems to attract a number of KDE users, Fluxbox is nice if you like minimalism, and there a bunch of others. Check out the monster screenshot thread in General and see if anything strikes your fancy.