os/bluestore: fix statfs to not include DB partition in free space

If we report the DB space as vailable, ceph thinks the OSD can store more
data and will not mark the cluster as full as easily.  And in reality, we
can't actually store data in this space--only metadata.  Avoid the problem
by not reporting it as available.

Fixes: http://tracker.ceph.com/issues/18599
Signed-off-by: Sage Weil <sage@redhat.com>

diff --git a/src/os/bluestore/BlueStore.cc b/src/os/bluestore/BlueStore.cc
index 2339948fc4ed2f5a1c3ab1b0cbde60fd17f2d239..be1218d9210173552cc5fde7e11d8e95e6efaeb4 100644 (file)
--- a/src/os/bluestore/BlueStore.cc
+++ b/src/os/bluestore/BlueStore.cc
@@ -4906,7 +4906,6 @@ int BlueStore::statfs(struct store_statfs_t *buf)
 
     // include dedicated db, too, if that isn't the shared device.
     if (bluefs_shared_bdev != BlueFS::BDEV_DB) {
-      buf->available += bluefs->get_free(BlueFS::BDEV_DB);
       buf->total += bluefs->get_total(BlueFS::BDEV_DB);
     }
   }