From: Michael Vrable <mvrable@cs.ucsd.edu>
Date: Thu, 9 Sep 2010 20:30:39 +0000 (-0700)
Subject: Allow cleaner to delete unused log segments.
X-Git-Url: https://git.vrable.net/?a=commitdiff_plain;h=2f883084c4393dc7b730df2e778b9f2fc14f70e0;p=bluesky.git

Allow cleaner to delete unused log segments.

It will not delete segments cleaned out in the current pass, just those
that were unreferenced at the start of the cleaning process.
---

diff --git a/cleaner/cleaner b/cleaner/cleaner
index 445bdeb..b018d0d 100755
--- a/cleaner/cleaner
+++ b/cleaner/cleaner
@@ -49,6 +49,9 @@ class FileBackend:
         fp.write(data)
         fp.close()
 
+    def delete(self, filename):
+        os.unlink(os.path.join(self.path, filename))
+
     def loc_to_name(self, location):
         return "log-%08d-%08d" % (location)
 
@@ -268,8 +271,10 @@ class InodeMap:
         print
         print "Segment utilizations:"
         for (s, u) in sorted(util.segments.items()):
-            #if u[1] > 0:
             print "%s: %s %s" % (s, u, float(u[1]) / u[0])
+            if u[1] == 0:
+                print "Deleting..."
+                backend.delete(s)
 
         self.inodes = inodes
         self.util = util
@@ -341,7 +346,7 @@ def run_cleaner(backend, inode_map, log):
     # 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] < 0.95 and u[1] > 0:
+        if float(u[1]) / u[0] < 0.6 and u[1] > 0:
             print "Should clean segment", s
             loc = backend.name_to_loc(s)
             if s: inode_map.obsolete_segments.add(loc)
@@ -381,7 +386,7 @@ if __name__ == '__main__':
     imap.build(backend, chkpt)
     print chkpt
 
-    log_dir = LogDirectory(backend, 1)
+    log_dir = LogDirectory(backend, 0)
     run_cleaner(backend, imap, log_dir)
     imap.write(backend, log_dir)
     log_dir.close_all()