archck kernel and cpu usage

PeteMo · 2006-01-29 15:48:48

I've recently installed the archck 2.6.15.archck2-4 kernel, and I've noticed a big jump in my cpu usage in Xwindows. With the default arch kernel, cpu usage at idle was 1-2%, in the archck kernel, it is around 40%, with X the major culprit at around 30%. This is on an IBM Thinkpad T40p with a 1.6MHz Pentium M processor, 512 MB ram, and an ATI Mobility Radeon 9000 video card. I am using the "ati" driver in xorg.conf.

I am fairly new to arch, and I was actually shocked when I booted into arch for the first time and saw such low cpu usage. In other distros - debian, ubuntu - I was accustomed to the ~40% usage the archck kernel shows.

It has actually crossed my mind that the stock arch kernel is simply causing a misreporting of cpu usage. Do you think this is the case or is it really the archck kernel? If so, what can I do to reduce the load on the cpu?

iphitus · 2006-01-30 05:41:43

Are you using ATI's driver?

Are you using blackbox?
One user on the CK mailing list had similar problems in blackbox.

iphitus

PeteMo · 2006-01-30 19:29:02

iphitus wrote:

Are you using ATI's driver?

No, not with either kernel.

iphitus wrote:

Are you using blackbox?
One user on the CK mailing list had similar problems in blackbox.

I am using enlightenment 0.16.8-pre3. I suppose that could be the issue. I was using this version of e16 in ubuntu, and saw the high cpu usage with their i686 kernel.

Any idea what differences between the stock arch kernel and the archck kernel might account for this? Is there anything I could try to troubleshoot this?

Cerebral · 2006-01-30 20:48:13

Now that you mention it, I remember I had massive CPU usage with X and e16 from the official repos... I'd use conky to monitor it, and X would always be loitering around 20-40% CPU. Now that I've switched to XFCE, when I check with conky, X isn't above 10%. (yes, I could use Top, but I figured maybe conky's a source of CPU usage, which it is... no conky + top X doesn't get above 2% with any frequency. )

If you're using the E16 pager with its screen-scraping to duplicate the look of the windows, that might be doing it. Try lowering the scan frequency of the pager or disabling that part of it altogether.

elasticdog · 2006-01-30 21:20:05

Is it normal to have CPU utilization that high even at idle?!? My machine is an XP-M 2500+ running Xfce and usually idles around 1%-2% with the stock kernel...which is what I would expect it to be. That's strange that it would vary so widely for people.

Cerebral · 2006-01-30 21:30:48

elasticdog wrote:

Is it normal to have CPU utilization that high even at idle?!? My machine is an XP-M 2500+ running Xfce and usually idles around 1%-2% with the stock kernel...which is what I would expect it to be. That's strange that it would vary so widely for people.

Well, I'd imagine that depends on whether your system really is idling. As in my example, I had both conky (upping CPU use by maybe 8%) and Enlightenment (I'm thinking it was the pager that tried to take snapshots of every desktop and update them at 25-50 lines/second -- forget what I had that set at) both running constantly, doing (what I suppose to be) non-trivial tasks.

So, in reality, my system rarely 'idled'.. now that I'm on XFCE and am using the button bar monitor plugins, CPU use is way down from that 20-40% I used to have.

PeteMo · 2006-01-31 00:36:20

I agree that at "idle" my computer is still doing stuff - conky, adesklets, probably a terminal window open. But what I'm noticing is that there is a significant difference in cpu usage between the stock arch kernel and the archck kerenl. All other factors are identical - same WM, same pager settings, same conky, same daemons, etc.

iphitus · 2006-01-31 07:06:02

This problem has been reported on the mailing list by one person, and as of yet nobody knows what exactly is causing it.

That person found that it only seemed to happen when he was using blackbox.

iphitus

iphitus · 2006-01-31 09:58:35

New archck is released, package is building now. Expect to see a new package coming down the chute in the next few days. It should fix this cpu usage problem.

PeteMo · 2006-01-31 11:04:22

iphitus wrote:

New archck is released, package is building now. Expect to see a new package coming down the chute in the next few days. It should fix this cpu usage problem.

Thanks a lot! I'll try it out and let you know how it goes.

Arch Linux

#1 2006-01-29 15:48:48

archck kernel and cpu usage

#2 2006-01-30 05:41:43

Re: archck kernel and cpu usage

#3 2006-01-30 19:29:02

Re: archck kernel and cpu usage

#4 2006-01-30 20:48:13

Re: archck kernel and cpu usage

#5 2006-01-30 21:20:05

Re: archck kernel and cpu usage

#6 2006-01-30 21:30:48

Re: archck kernel and cpu usage

#7 2006-01-31 00:36:20

Re: archck kernel and cpu usage

#8 2006-01-31 07:06:02

Re: archck kernel and cpu usage

#9 2006-01-31 09:58:35

Re: archck kernel and cpu usage

#10 2006-01-31 11:04:22

Re: archck kernel and cpu usage

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