mirror of
https://git.proxmox.com/git/mirror_zfs.git
synced 2026-05-22 02:27:36 +03:00
Alexander Motin
d151432073
When ZIL allocates space for new LWBs without knowing how much it will require, it can use new metaslab_alloc_range() function to allocate slightly more or less than it predicted. It allows to improve space efficiency by allocating bigger LWBs on RAIDZ/dRAID instead of padding and possibly packing more ZIL records there. It may also allow to reduce ganging in some cases by allowing to allocate smaller LWBs when we are not sure we'll need bigger. On the opposite side, when we allocate space for already closed LWBs, when we precisely know how much space we need, we may just allocate what we need instead of relying on writing less than allocated, that does not work for RAIDZ. Space for LWBs in open state (still being filled) is allocated same as before. Reviewed-by: Rob Norris <robn@despairlabs.com> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Alexander Motin <alexander.motin@TrueNAS.com> Closes #17613