cp slows entire computer down

Jonhoo · 2011-05-14 19:07:53

Hi fellow Archers!

I've been bugged by an annoying problem lately - whenever I try to do a large copy operation (large files/many files), my CPU usage goes through the roof.
This happens both with internal -> eSATA and eSATA -> USB.
Top shows cp using about 5% CPU, and several "kworker" processes using 25-35% each!

Any idea what might be causing this?
Seems similar to https://bbs.archlinux.org/viewtopic.php?pid=658003 which was never resolved.

Thanks for any input,
Jon

Markus00000 · 2011-06-25 12:48:30

You might want to read or subscribe to these more or less similar issues:
https://bbs.archlinux.org/viewtopic.php?id=112752 (see page 2 for reloading usb modules and booting with "pcie_ports=compat")
https://bbs.archlinux.org/viewtopic.php?id=109371

Markus00000 · 2011-06-26 07:34:33

In case you are using the 64-bit version, you might want to consider installing the 32-bit version. I have both installed and the 32-bit version does not have any crazy kworkers.

graysky · 2011-06-26 07:40:53

Don't abandon x86_64 - particularly if you have >= 3 gigs of memory! I had this problem using the stock ARCH kernel and found that it all but disappeared running kernel26-ck (more efficient scheduler for desktops). You can give it a try in the AUR or from my unofficial repo. See my sig.

Last edited by graysky (2011-06-26 07:41:14)

Markus00000 · 2011-06-26 12:51:01

Thanks, I will give it a try. Well, I didn't abandon x86_64, I simply dual boot. I don't care that much as I have < 3GB of memory.

Edit: Gave it a try. When copying from USB to internal hard drive with kernel26-ck and BFQ, kswapd0 takes 15-20% CPU and the system is as unresponsive as before.

Last edited by Markus00000 (2011-06-26 13:30:56)

Markus00000 · 2011-06-26 13:13:45

graysky wrote:

kernel26-ck (more efficient scheduler for desktops)

Is there a reason why the wiki article in your signature doesn't mention adding "elevator=bfq" to /boot/grub/menu.lst? Shouldn't this enable the BFQ scheduler for USB disks as well? Or won't this work as BFQ is a module?

Last edited by Markus00000 (2011-06-26 13:14:43)

graysky · 2011-06-26 13:48:16

Yeah, see https://bbs.archlinux.org/viewtopic.php?id=111715&p=13
I might have to re-think compiling it into the kernel for folk who want it for USB disks... perhaps I'll make that change in the 2.6.39.2 release which should be any time now. Just waiting on the ARCH patchset.

Arch Linux

#1 2011-05-14 19:07:53

cp slows entire computer down

#2 2011-06-25 12:48:30

Re: cp slows entire computer down

#3 2011-06-26 07:34:33

Re: cp slows entire computer down

#4 2011-06-26 07:40:53

Re: cp slows entire computer down

#5 2011-06-26 12:51:01

Re: cp slows entire computer down

#6 2011-06-26 13:13:45

Re: cp slows entire computer down

#7 2011-06-26 13:48:16

Re: cp slows entire computer down

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