[Bug-xorriso] Xorriso slow in ISO creation

[Wei Liu]

Hi all

This is not a bug, just something I observe when I use Xorriso. Thought
you might have some advice.

We recently switch from genisoimage to xorriso. In both cases we use the
packaged software in Debian Wheezy. Xorriso is 1.2.2., genisoimage is
1.1.11.

My colleague's quick test result.

  $ time xorriso -as mkisofs -R -J -o xorriso.iso xen -- -changes_pending yes
  [...]
  real    0m1.389s
  user    0m0.192s
  sys     0m0.264s
  
  $ time genisoimage -o genisoimage.iso -R -J xen
  real    0m0.395s
  user    0m0.220s
  sys     0m0.168s

(Directory xen contains ~100M random stuffs)

We don't quite understand why Xorriso is so much slower then
genisoimage. Is there something wrong with the parameter we're using?
Are we missing something?

(I don't subscribe to this list, so please keep me CC'ed when you reply)

Thanks
Wei.