Feature #7059
Updated by Sage Weil over 10 years ago
The current FileStore code calls into DBObjectMap for xattrs in many cases unconditionally. This means taht even for objects that have only a few xattrs (that the fs can handle on its own in the inode), we are also hitting leveldb and possibly suffering some slowdown.
Instead, have a small xattr on the fs inode that indicates whether we should look in leveldb at all. I see two ways do to this:
- a flag on the FileStore, set on creation, that indicates whether such xattrs are present.
- if set, only look at DBObjectMap if the xattr is there. otherwise, we can skip it (e.g., on delete).
or
- unconditionally maintain an xattr that indicates whether we spill over into DBObjectMap.
- if not present, assume this is an old store/object and look in DBObjectMap unconditionally (as we do now)
Care would need to be taken that we adjust the attr when we transition from fs-only to fs + DBObjectMap and back.
Other suggestions?