system slow while copying big files

[portia]

Hi,

I don't know if that's the right section of the forum.
While I'm copying big files (or a lot of files) the system gets so slow that it's hardly usable. It's a modern laptop with 3GB of RAM. I'm using Slackware 13.
Something must be wrong with my system.
Thanks for any help

[tpl]

try putting the copy down a little: use "nice"

[coopstah13]

Probably what is happening is you have maxed out your disk transfer and anything else you try to access from disk will subsequently be slowed severely.

[portia]

Thanks for your replies.
If that's the maximum my system can reach, fine. I'll have to decrease the priority of copy using nice. I don't mind if it copies slower, as long as I can do other things in the meantime.
I've heard about 'nice' before, I'll need to google some info about it.

[coopstah13]

You can see if you are IO bound fairly simply.
Open a terminal and execute iostat -d -x 5 and watch output while running your copy. You can also use vmstat 5 and watch the last column, this is iowait time.

[Rubberman]

The same thing happens on my Linux systems when I copy big files around. It basically becomes I/O bound. I have a CentOS 5.4 system with 10 sata drives installed (about 10TB total) and this happens to me when I'm copying a bunch of big files (DVD ISO images for example) as well. I'm not sure there's much you can do about that. I find that if I do the copy externally from the GUI, such as using cp/mv from a command line, that the impact isn't as severe as doing it from the GUI file manager such as konqueror (KDE), so it might not just be an I/O situation as overloading the GUI subsystem as well. FWIW, I have an 8 core system with 8GB RAM and both internal SATA controller as well as a PCI-X esata controller, and neither the CPU nor the RAM are overloaded in these cases. The data moves at maximum disc speed in any case.