On Sun, 26 Jun 2011, Ted Ts'o wrote:

On Sun, Jun 26, 2011 at 12:33:16PM -0500, Mccauliff, Sean D. (ARC-PX)[Lockheed Martin Space OPNS] wrote:

quoted

Sorry if this is not the correct mailing list for ext4 questions.

-ext3-users, +linux-ext4

quoted

I'm copying terabytes of data from an ext3 file system to a new ext4
file system.  I'm seeing high CPU usage from the processes
flush-253:2, kworker-3:0, kworker-2:2, kworker-1:1, and kworker-0:0.
Does anyone on the list have any idea what these processes do, why
they are consuming so much cpu time and if there is something that
can be done about it?  This is using Fedora 15.

You're using Fedora 15, so you're using a 2.6.38 kernel, right?

How are you copying the files?  Are you using cp?  rsync?  NFS?  CIFS?

what sort of files are you copying?  Are they large files, many of
small files?   Are there lots of hard links?  etc.

      	       	   	      	      - Ted

Also, how high is high CPU usage ? Is ext4lazyinit thread running (ps
aux | grep ext4lazyinit) ? If it is could you try to mount it with '-o
noinit_itable' mount option to see if it helps ?


Thanks!
-Lukas