diff --git a/subcmds/sync.py b/subcmds/sync.py
index 82056f3..ef02327 100644
--- a/subcmds/sync.py
+++ b/subcmds/sync.py
@@ -64,6 +64,7 @@
 except ImportError:
   multiprocessing = None
 
+import event_log
 from git_command import GIT, git_require
 from git_config import GetUrlCookieFile
 from git_refs import R_HEADS, HEAD
@@ -304,9 +305,10 @@
     # - We always set err_event in the case of an exception.
     # - We always make sure we call sem.release().
     # - We always make sure we unlock the lock if we locked it.
+    start = time.time()
+    success = False
     try:
       try:
-        start = time.time()
         success = project.Sync_NetworkHalf(
           quiet=opt.quiet,
           current_branch_only=opt.current_branch_only,
@@ -345,6 +347,9 @@
     finally:
       if did_lock:
         lock.release()
+      finish = time.time()
+      self.event_log.AddSync(project, event_log.TASK_SYNC_NETWORK,
+                             start, finish, success)
 
     return success
 
@@ -720,16 +725,24 @@
       _PostRepoUpgrade(self.manifest, quiet=opt.quiet)
 
     if not opt.local_only:
-      mp.Sync_NetworkHalf(quiet=opt.quiet,
-                          current_branch_only=opt.current_branch_only,
-                          no_tags=opt.no_tags,
-                          optimized_fetch=opt.optimized_fetch,
-                          submodules=self.manifest.HasSubmodules)
+      start = time.time()
+      success = mp.Sync_NetworkHalf(quiet=opt.quiet,
+                                    current_branch_only=opt.current_branch_only,
+                                    no_tags=opt.no_tags,
+                                    optimized_fetch=opt.optimized_fetch,
+                                    submodules=self.manifest.HasSubmodules)
+      finish = time.time()
+      self.event_log.AddSync(mp, event_log.TASK_SYNC_NETWORK,
+                             start, finish, success)
 
     if mp.HasChanges:
       syncbuf = SyncBuffer(mp.config)
+      start = time.time()
       mp.Sync_LocalHalf(syncbuf, submodules=self.manifest.HasSubmodules)
-      if not syncbuf.Finish():
+      clean = syncbuf.Finish()
+      self.event_log.AddSync(mp, event_log.TASK_SYNC_LOCAL,
+                             start, time.time(), clean)
+      if not clean:
         sys.exit(1)
       self._ReloadManifest(manifest_name)
       if opt.jobs is None:
@@ -823,7 +836,10 @@
     for project in all_projects:
       pm.update()
       if project.worktree:
+        start = time.time()
         project.Sync_LocalHalf(syncbuf, force_sync=opt.force_sync)
+        self.event_log.AddSync(project, event_log.TASK_SYNC_LOCAL,
+                               start, time.time(), syncbuf.Recently())
     pm.end()
     print(file=sys.stderr)
     if not syncbuf.Finish():
@@ -907,6 +923,7 @@
     return False
   return True
 
+
 class _FetchTimes(object):
   _ALPHA = 0.5