log.write(new_checkpoint, 2)
self.checkpoint_record = new_checkpoint
-def rewrite_inode(backend, inode_map, inum, log):
+def rewrite_inode(backend, inode_map, inum, log, copy_data=True):
inode = inode_map.inodes[inum]
- blocks = []
- for l in inode.links:
- data = load_item(backend, l[1])
- blocks.append(data)
- log.write(data, 0)
- inode.links = [(b.id, b.location) for b in blocks]
+ if copy_data:
+ blocks = []
+ for l in inode.links:
+ data = load_item(backend, l[1])
+ blocks.append(data)
+ log.write(data, 0)
+ inode.links = [(b.id, b.location) for b in blocks]
log.write(inode, 1)
inode_map.mark_updated(inum)
# Determine which segments are poorly utilized and should be cleaned. We
# need better heuristics here.
for (s, u) in sorted(inode_map.util.segments.items()):
- if float(u[1]) / u[0] < 0.99 and u[1] > 0:
+ if float(u[1]) / u[0] < 0.95 and u[1] > 0:
print "Should clean segment", s
loc = backend.name_to_loc(s)
if s: inode_map.obsolete_segments.add(loc)
+ # TODO: We probably also want heuristics that will find inodes with
+ # badly-fragmented data and rewrite that to achieve better locality.
+
# Given that list of segments to clean, scan through those segments to find
# data which is still live and mark relevant inodes as needing to be
# rewritten.
dirty_inodes = set()
+ dirty_inode_data = set()
for s in inode_map.obsolete_segments:
filename = backend.loc_to_name(s)
print "Scanning", filename, "for live data"
for item in parse_log(backend.read(filename), filename):
if item.type in (ITEM_TYPE.DATA, ITEM_TYPE.INODE):
if item.inum != 0:
- dirty_inodes.add(item.inum)
+ inode = inode_map.inodes[item.inum]
+ if s == inode.location[0:2]:
+ dirty_inodes.add(item.inum)
+ if item.inum not in dirty_inode_data:
+ for b in inode.links:
+ if s == b[1][0:2]:
+ dirty_inode_data.add(item.inum)
+ break
print "Inodes to rewrite:", dirty_inodes
- for i in sorted(dirty_inodes):
- rewrite_inode(backend, inode_map, i, log)
+ print "Inodes with data to rewrite:", dirty_inode_data
+ for i in sorted(dirty_inodes.union(dirty_inode_data)):
+ rewrite_inode(backend, inode_map, i, log, i in dirty_inode_data)
if __name__ == '__main__':
backend = FileBackend(".")
imap.build(backend, chkpt)
print chkpt
- log_dir = LogDirectory(backend, 0)
+ log_dir = LogDirectory(backend, 1)
run_cleaner(backend, imap, log_dir)
imap.write(backend, log_dir)
log_dir.close_all()