diff --git a/tests/test_warcprox.py b/tests/test_warcprox.py
index 95c8aba..abc373a 100755
--- a/tests/test_warcprox.py
+++ b/tests/test_warcprox.py
@@ -84,7 +84,8 @@ def _send(self, data):
 # http_client.HTTPConnection.send = _send
 
 logging.basicConfig(
-        stream=sys.stdout, level=logging.DEBUG, # level=warcprox.TRACE,
+        # stream=sys.stdout, level=logging.DEBUG, # level=warcprox.TRACE,
+        stream=sys.stdout, level=warcprox.TRACE,
         format='%(asctime)s %(process)d %(levelname)s %(threadName)s '
         '%(name)s.%(funcName)s(%(filename)s:%(lineno)d) %(message)s')
 logging.getLogger("requests.packages.urllib3").setLevel(logging.WARN)
@@ -424,6 +425,7 @@ def test_dedup_http(http_daemon, warcprox_, archiving_proxies, playback_proxies)
     # {u'id': u'<urn:uuid:e691dc0f-4bb9-4ad8-9afb-2af836aa05e4>', u'url': u'https://localhost:62841/c/d', u'date': u'2013-11-22T00:14:37Z'}
     dedup_lookup = warcprox_.warc_writer_threads[0].dedup_db.lookup(
             b'sha1:65e1216acfd220f0292715e74bd7a1ec35c99dfc')
+    assert dedup_lookup
     assert dedup_lookup['url'] == url.encode('ascii')
     assert re.match(br'^<urn:uuid:[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}>$', dedup_lookup['id'])
     assert re.match(br'^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}Z$', dedup_lookup['date'])
@@ -497,6 +499,7 @@ def test_dedup_https(https_daemon, warcprox_, archiving_proxies, playback_proxie
     # {u'id': u'<urn:uuid:e691dc0f-4bb9-4ad8-9afb-2af836aa05e4>', u'url': u'https://localhost:62841/c/d', u'date': u'2013-11-22T00:14:37Z'}
     dedup_lookup = warcprox_.warc_writer_threads[0].dedup_db.lookup(
             b'sha1:5b4efa64fdb308ec06ae56a9beba155a6f734b89')
+    assert dedup_lookup
     assert dedup_lookup['url'] == url.encode('ascii')
     assert re.match(br'^<urn:uuid:[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}>$', dedup_lookup['id'])
     assert re.match(br'^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}Z$', dedup_lookup['date'])
diff --git a/warcprox/dedup.py b/warcprox/dedup.py
index 4206f26..78a8214 100644
--- a/warcprox/dedup.py
+++ b/warcprox/dedup.py
@@ -322,17 +322,30 @@ class TroughDedupDb(object):
     def __init__(self, options=warcprox.Options()):
         self.options = options
         self._trough_cli = TroughClient(options.rethinkdb_trough_db_url)
+        self._write_url_cache = {}
+        self._read_url_cache = {}
 
     def start(self):
         self._trough_cli.register_schema(self.SCHEMA_ID, self.SCHEMA_SQL)
 
     def _write_url(self, bucket):
-        segment_id = 'warcprox-trough-%s' % bucket
-        return self._trough_cli.write_url(segment_id, self.SCHEMA_ID)
+        if not bucket in self._write_url_cache:
+            segment_id = 'warcprox-trough-%s' % bucket
+            self._write_url_cache[bucket] = self._trough_cli.write_url(
+                    segment_id, self.SCHEMA_ID)
+            logging.info(
+                    'bucket %r write url is %r', bucket,
+                    self._write_url_cache[bucket])
+        return self._write_url_cache[bucket]
 
     def _read_url(self, bucket):
-        segment_id = 'warcprox-trough-%s' % bucket
-        return self._trough_cli.read_url(segment_id)
+        if not self._read_url_cache.get(bucket):
+            segment_id = 'warcprox-trough-%s' % bucket
+            self._read_url_cache[bucket] = self._trough_cli.read_url(segment_id)
+            logging.info(
+                    'bucket %r read url is %r', bucket,
+                    self._read_url_cache[bucket])
+        return self._read_url_cache[bucket]
 
     def sql_value(self, x):
         if x is None:
@@ -371,6 +384,8 @@ class TroughDedupDb(object):
             logging.warn(
                     'unexpected response %r %r %r to sql=%r',
                     response.status_code, response.reason, response.text, sql)
+        else:
+            logging.trace('posted %r to %s', sql, write_url)
 
     def lookup(self, digest_key, bucket='__unspecified__', url=None):
         read_url = self._read_url(bucket)