[PATCH 10/12] btrfs: make smaller extents more likely to go into bitmaps

Dennis Zhou
2020-01-02T21:27:05Z

It's less than ideal for small extents to eat into our extent budget, so
force extents <= 32KB into the bitmaps save for the first handful.

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
---
fs/btrfs/free-space-cache.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index 665f6eb6c828..6d74d96a1d13 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -2107,8 +2107,8 @@ static bool use_bitmap(struct btrfs_free_space_ctl *ctl,
* of cache left then go ahead an dadd them, no sense in adding
* the overhead of a bitmap if we don't have to.
*/
- if (info->bytes <= fs_info->sectorsize * 4) {
- if (ctl->free_extents * 2 <= ctl->extents_thresh)
+ if (info->bytes <= fs_info->sectorsize * 8) {
+ if (ctl->free_extents * 3 <= ctl->extents_thresh)
return false;
} else {
return false;
--
2.17.1