zfs/module
Pawel Jakub Dawidek 0cee24064a Speed up 'zfs list -t snapshot -o name -s name'
FreeBSD #xxx:  Dramatically optimize listing snapshots when user
requests only snapshot names and wants to sort them by name, ie.
when executes:

  # zfs list -t snapshot -o name -s name

Because only name is needed we don't have to read all snapshot
properties.

Below you can find how long does it take to list 34509 snapshots
from a single disk pool before and after this change with cold and
warm cache:

    before:

        # time zfs list -t snapshot -o name -s name > /dev/null
        cold cache: 525s
        warm cache: 218s

    after:

        # time zfs list -t snapshot -o name -s name > /dev/null
        cold cache: 1.7s
        warm cache: 1.1s

NOTE: This patch only appears in FreeBSD.  If/when Illumos picks up
the change we may want to drop this patch and adopt their version.
However, for now this addresses a real issue.

Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #450
2012-06-14 09:49:04 -07:00
..
avl Support custom build directories and move includes 2010-09-08 12:38:56 -07:00
nvpair Implement SA based xattrs 2011-11-28 15:45:51 -08:00
unicode Support custom build directories and move includes 2010-09-08 12:38:56 -07:00
zcommon Support ashift=13 for 8KB SSD block sizes 2012-02-13 12:25:27 -08:00
zfs Speed up 'zfs list -t snapshot -o name -s name' 2012-06-14 09:49:04 -07:00
zpios Linux 2.6.36 compat, use fops->unlocked_ioctl() 2010-11-10 17:01:08 -08:00
.gitignore Add .gitignore files to exclude build products 2010-01-08 11:35:17 -08:00
Makefile.in Fix 'make install' overly broad 'rm' 2011-07-20 09:38:51 -07:00