Limit total logs imported at once

Postgres really dislikes when you try and import too many logs at once
(thus grabbing too many logs). In addition to our minute-long commit
interval, also limit ourselves to 500 commits. With 256 locks per
transaction, I made it to 850 logs or so until I got kicked out, so 500
should be well within limits.

Signed-off-by: Sean Anderson <[email protected]>

import.py

@@ -722,7 +722,7 @@ def commit():
             count += 1
 
         now = datetime.now()
-        if (now - start).total_seconds() > 60:
+        if (now - start).total_seconds() > 60 or count > 500:
             commit()
             logging.info("Committed %s imported log(s)...", count)
             cur.execute("BEGIN;")