Way to prune/limit the ZFS zpool history?

[Geoff Fritz]

On Tue, Jan 20, 2009 at 10:17:47PM -0600, Dan Nelson wrote:
> In the last episode (Jan 20), Geoff Fritz said:
> > I've been experimenting with a series scripts that takes ZFS
> > snapshots every minute, eventually destroying the oldest so that only
> > so many remain available for a given window of time.
> > 
> > This may seem a trivial concern with hard drive sizes being what they
> > are these days, but after running a "zpool history" I started
> > thinking that a ZFS create and destroy being performed every minute
> > would add up to a lot over the course of a few years (current
> > estimate is 62MB/year for the naming scheme of my snapshots).
> 
> According to
> http://docs.sun.com/app/docs/doc/819-5461/gdswe?l=en&a=view , the zpool
> history file is between 128K and 32MB, depending on the size of the
> pool.  The FreeBSD import at
> /sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa_history.c agrees
> with the docs :)

I always forget that ZFS is documented on Sun's site as well as the man pages.
Hopefully some day the FreeBSD docs will catch up w/ Sun's.

Thanks a bunch for the pointer.  Very informative.

-- Geoff