Alok Aggarwal's Weblog

Monday March 09, 2009

Serving Up Lzma

I just pushed the changes that add LZMA to (Open)Solaris
and also allow lofi(7D) to use LZMA as one of the
supported compression algorithms.

On an snv_111 machine, here's what you will see -

Usage: lofiadm -a file [ device ]
       [-c aes-128-cbc|aes-192-cbc|aes-256-cbc|des3-cbc|blowfish-cbc]
       [-e] [-k keyfile] [-T[token]:[manuf]:[serial]:key]
       lofiadm -d file | device
       lofiadm -C [gzip|gzip-6|gzip-9|lzma] [-s segment_size] file
       lofiadm -U file
       lofiadm [ file | device ]

So, if you take large'ish file and compress it with gzip
and lzma, the size difference is quite noticeable.

contraption# du -h solaris.orig
 2.2G   solaris.orig
contraption# lofiadm -C lzma solaris.orig
contraption# du -h solaris.orig
 555M   solaris.orig
contraption# lofiadm -U solaris.orig
contraption# lofiadm -C gzip solaris.orig
contraption# du -h solaris.orig
 702M   solaris.orig

With LZMA support now available for both userland and
kernel consumers, it should be very easy for other Solaris
utilities (zfs?) to provide support for it.

( Mar 10 2009, 03:38:07 PM EDT / Mar 09 2009, 02:44:26 PM EDT ) Permalink Comments [4]
Trackback: http://blogs.sun.com/aalok/entry/serving_up_lzma

Comments:

Phenomenal!!!

This is great, because LZMA provides the best compression currently known to humans!

It should only be a matter of time now, with lzma being in the kernel, before booting from a LZMA-compressed zpool becomes possible.

The implications and the possibilities are mind boggling, from compressed zpools to Oracle data warehouses...

Thank you, thank you, thank you. You rule!

Posted by UX-admin on March 10, 2009 at 11:13 AM EDT #

Hi,

awesome work!
Just a note about lofiadm, you may like to get ride of:
lofiadm: illegal option -- h

when the help -h switch is used. It looks clear!
Thanks,
Edward.

Posted by Edward O'Callaghan on March 10, 2009 at 11:21 AM EDT #

@Edward: Good suggestion, I've taken out the -h from the post.

Posted by Alok Aggarwal on March 10, 2009 at 03:40 PM EDT #

I'm working on lzma support in ZFS. First cut at the code too less than 10 minutes - will see if it works when my build finishes!

Posted by Darren Moffat on March 13, 2009 at 07:11 AM EDT #