Currently v1 space cache clearing will delete one cache inode just in
one transaction, and then start a new transaction to delete the next
inode.
This is far from efficient and can make the already slow v1 space cache
deleting even slower, as large fs has tons of cache inodes to delete.
This patch will speed up the process by batching up to 16 inode deletion
into one transaction.
A quick benchmark of deleting 702 v1 space cache inodes would look like
this:
Unpatched: 4.898s
Patched: 0.087s
Which is obviously a big win.
Reported-by: Joshua <joshua@mailmag.net>
Link: https://lore.kernel.org/linux-btrfs/0b4cf70fc883e28c97d893a3b2f81b11@mailmag.net/
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
