freebsd-dev/module
Brian Behlendorf 7fc8c33ede Don't read space maps during import for readonly pools
Normally when importing a pool the space maps for all top level
vdevs are read from disk.  The space maps will be required latter
when an allocation is performed and free blocks need to be located.

However, if the pool is imported readonly then we are guaranteed
that no allocations can occur.  In this case the space maps need
not be loaded..   A similar argument can be made for the DTLs
(dirty time logs).

Because a pool import will fail if the space maps cannot be read.
The ability to safely ignore them makes it more likely that a
damaged pool can be imported readonly to recover its contents.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2831
2015-02-09 16:43:03 -08:00
..
avl Explicitly include SPL compat headers 2014-11-19 12:30:39 -05:00
nvpair Retire KM_NODEBUG 2015-01-16 14:40:32 -08:00
unicode Explicitly include SPL compat headers 2014-11-19 12:30:39 -05:00
zcommon Change KM_PUSHPAGE -> KM_SLEEP 2015-01-16 14:41:26 -08:00
zfs Don't read space maps during import for readonly pools 2015-02-09 16:43:03 -08:00
zpios Explicitly include SPL compat headers 2014-11-19 12:30:39 -05:00
.gitignore gitignore: anchor entries at their respective directory 2013-04-02 10:50:17 -07:00
Makefile.in Fix modules installation directory 2014-10-28 09:46:14 -07:00