cpio to ext4 seems much slower than to ext2, ext3 or xfs

[Richard W.M. Jones]

On Wed, Nov 11, 2009 at 10:14:21AM +0000, Richard W.M. Jones wrote:
>   echo input | time cpio --quiet -o -H newc > /path/to/fs/output

Update: I found the -C option that lets me specify the blocksize, and
raising it to something sensible (65536) shows major improvements in
performance for all filesystems.  

  echo input | time cpio -C 65536 --quiet -o -H newc > /path/to/fs/output

>   tmpfs      0.77 s    x 1.0
>   ext2       1.12 s    x 1.5
>   xfs        1.66 s    x 2.1
>   ext3       2.58 s    x 3.4
>   ext4       5.59 s    x 7.3    <----

The new times are:

  tmpfs     0.20 s    x 1.0
  ext2      0.30 s    x 1.5
  xfs       0.41 s    x 2.1
  ext3      0.57 s    x 2.9
  ext4      0.44 s    x 2.2

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
New in Fedora 11: Fedora Windows cross-compiler. Compile Windows
programs, test, and build Windows installers. Over 70 libraries supprt'd
http://fedoraproject.org/wiki/MinGW http://www.annexia.org/fedora_mingw