So dpkg fsync()'s the file and the directory containing the file whenever it
writes to a file which is really slow in btrfs. This is partly because
fsync()'ing a directory _always_ committed the transaction instead of just
going to the tree log. This is because drop_objectid_items() would return 1
since it does a btrfs_search_slot() which returns 1. In tree-log jargon
this means that we have to commit the transaction to be safe. So just check
if ret is greater than 0 and set it to 0 if it does. With this patch we now
use the tree-log instead of committing the entire transaction, which is
twice as fast on my box. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
5bdbeb2187