ZFS LZ4 Upgrade

[John Nielsen]

On Jun 3, 2013, at 12:52 PM, Kenta Suzumoto <kentas at hush.com> wrote:

> Hi. I'm planning on doing a ZFS root installation on a remote server very soon. The company only offers a 9.0 and 9.1 installation and "rescue" (nfs/pxe boot with ramdisk basically) system. I'd like to use LZ4 with the ZFS root pool, so I'm going to be upgrading to -STABLE once I have the initial system installed. Here's what I'll do:
> 
> - install the 9.1 system
> - svn source, buildworld/kernel, install, reboot
> - upon booting the -STABLE system, begin enabling LZ4 compression on /usr/ports /usr/src etc.
> 
> Will this work, or do I need to find some way to initially create the zpool with a -STABLE system? Is it just a matter of running "zfs upgrade" and "zpool upgrade" before enabling LZ4, or am I missing something? Thanks

That should work. Just keep in mind that blocks written before you enable compression won't be compressed. So you may want to create a _new_ ZFS for src (and ports if it already exists as well) after your source upgrade, then copy the contents of /usr/src over to it. (Then update the mountpoints as desired, etc.)

JN