From 3361e337c993f58adefddbf52621e5197229bb84 Mon Sep 17 00:00:00 2001
From: Michael Vrable <mvrable@cs.ucsd.edu>
Date: Fri, 10 Dec 2010 15:02:15 -0800
Subject: [PATCH] Commit a basic but functional online cleaner implementation.

The cleaner needn't be aware of parallelism; the proxy will handle merging
of data.
---
 bluesky/bluesky-private.h |  1 +
 bluesky/cleaner.c         | 46 +++++++++++++++++++++++++++++++++++++++
 bluesky/inode.c           |  2 +-
 cleaner/cleaner           |  2 +-
 4 files changed, 49 insertions(+), 2 deletions(-)

diff --git a/bluesky/bluesky-private.h b/bluesky/bluesky-private.h
index b188ac2..be7a2d3 100644
--- a/bluesky/bluesky-private.h
+++ b/bluesky/bluesky-private.h
@@ -477,6 +477,7 @@ gboolean bluesky_checkpoint_load(BlueSkyFS *fs);
 
 /* Merging of log state with the work of the cleaner. */
 void bluesky_cleaner_merge(BlueSkyFS *fs);
+void bluesky_cleaner_thread_launch(BlueSkyFS *fs);
 
 #ifdef __cplusplus
 }
diff --git a/bluesky/cleaner.c b/bluesky/cleaner.c
index d7e29eb..0fc39df 100644
--- a/bluesky/cleaner.c
+++ b/bluesky/cleaner.c
@@ -155,6 +155,8 @@ static BlueSkyCleanerItem *bluesky_cleaner_find_checkpoint(BlueSkyFS *fs)
     g_mutex_unlock(cachefile->lock);
 
     BlueSkyCleanerItem *checkpoint = bluesky_cleaner_deserialize(data);
+    checkpoint->location.directory = BLUESKY_CLOUD_DIR_CLEANER;
+    checkpoint->location.directory = seq;
     bluesky_string_unref(data);
 
     return checkpoint;
@@ -200,6 +202,29 @@ gboolean needs_merging(BlueSkyFS *fs, BlueSkyCloudPointer location)
     return TRUE;
 }
 
+/* For an inode which has been modified by the cleaner and must be flushed out
+ * to cloud storage, mark it as appropriately dirty.  We will bypass writingt
+ * the inode to the journal if possible--but if there have ben other
+ * uncommitted changes besides what the cleaner did then we will force a
+ * journal write as well since the cloud shouldn't contain newer data than the
+ * journal.  Inode must be locked. */
+static void cleaner_flush_inode(BlueSkyInode *inode)
+{
+    // if (inode->change_commit != inode->change_count) {
+    if (TRUE) {
+        /* bluesky_inode_start_sync schedules a flush to the cloud so we're all
+         * done. */
+        bluesky_inode_start_sync(inode);
+        return;
+    }
+
+    g_assert(inode->unlogged_list == NULL);
+
+    bluesky_list_unlink(&inode->fs->dirty_list, inode->dirty_list);
+    inode->dirty_list = bluesky_list_prepend(&inode->fs->dirty_list, inode);
+    inode->change_cloud = inode->change_count;
+}
+
 static void merge_inode(BlueSkyFS *fs, BlueSkyCleanerItem *cleaner_inode)
 {
     /* There are two versions we are concerned with: cleaner_ is for the data
@@ -254,6 +279,7 @@ static void merge_inode(BlueSkyFS *fs, BlueSkyCleanerItem *cleaner_inode)
             b->ref->location = cb->location;
         }
     }
+    cleaner_flush_inode(proxy_inode);
     g_mutex_unlock(proxy_inode->lock);
 
     /* Mark the inode as modified so it will get written back to the cloud.  We
@@ -305,5 +331,25 @@ void bluesky_cleaner_merge(BlueSkyFS *fs)
         bluesky_cleaner_item_free(imap);
     }
 
+    fs->log_state->latest_cleaner_seq_seen = checkpoint->location.directory;
     bluesky_cleaner_item_free(checkpoint);
 }
+
+/* Run the cleaner as a background task. */
+static gpointer cleaner_thread(BlueSkyFS *fs)
+{
+    while (TRUE) {
+        struct timespec delay;
+        delay.tv_sec = 30;
+        delay.tv_nsec = 0;
+        nanosleep(&delay, NULL);
+        bluesky_cleaner_merge(fs);
+    }
+
+    return NULL;
+}
+
+void bluesky_cleaner_thread_launch(BlueSkyFS *fs)
+{
+    g_thread_create((GThreadFunc)cleaner_thread, fs, FALSE, NULL);
+}
diff --git a/bluesky/inode.c b/bluesky/inode.c
index dd20cc9..cabaa34 100644
--- a/bluesky/inode.c
+++ b/bluesky/inode.c
@@ -132,7 +132,7 @@ BlueSkyFS *bluesky_init_fs(gchar *name, BlueSkyStore *store,
         bluesky_inode_do_sync(root);
     }
 
-    bluesky_cleaner_merge(fs);
+    bluesky_cleaner_thread_launch(fs);
 
     return fs;
 }
diff --git a/cleaner/cleaner b/cleaner/cleaner
index 675819b..c7b3d84 100755
--- a/cleaner/cleaner
+++ b/cleaner/cleaner
@@ -473,7 +473,7 @@ def run_cleaner(backend, inode_map, log, repack_inodes=False):
     # 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] < 0.6 or u[1] < 32768) 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)
-- 
2.20.1