Merge pull request #562 from matrix-org/erikj/push_metric

Add metrics to pushers

3 files changed, 149 insertions, 31 deletions

diff --git a/synapse/http/server.py b/synapse/http/server.py
index c250a4604f..06935783ca 100644
--- a/synapse/http/server.py
+++ b/synapse/http/server.py
@@ -208,6 +208,9 @@ class JsonResource(HttpServer, resource.Resource):
         if request.method == "OPTIONS":
             self._send_response(request, 200, {})
             return
+
+        start_context = LoggingContext.current_context()
+
         # Loop through all the registered callbacks to check if the method
         # and path regex match
         for path_entry in self.path_regexs.get(request.method, []):
@@ -243,6 +246,13 @@ class JsonResource(HttpServer, resource.Resource):
                 if context:
                     tag = context.tag
 
+                    if context != start_context:
+                        logger.warn(
+                            "Context have unexpectedly changed %r, %r",
+                            context, self.start_context
+                        )
+                        return
+
                 incoming_requests_counter.inc(request.method, servlet_classname, tag)
 
                 response_timer.inc_by(
diff --git a/synapse/push/__init__.py b/synapse/push/__init__.py
index 8b9d0f03e5..64e581b8ba 100644
--- a/synapse/push/__init__.py
+++ b/synapse/push/__init__.py
@@ -17,6 +17,8 @@ from twisted.internet import defer
 
 from synapse.streams.config import PaginationConfig
 from synapse.types import StreamToken
+from synapse.util.logcontext import LoggingContext
+from synapse.util.metrics import Measure
 
 import synapse.util.async
 import push_rule_evaluator as push_rule_evaluator
@@ -27,6 +29,16 @@ import random
 logger = logging.getLogger(__name__)
 
 
+_NEXT_ID = 1
+
+
+def _get_next_id():
+    global _NEXT_ID
+    _id = _NEXT_ID
+    _NEXT_ID += 1
+    return _id
+
+
 # Pushers could now be moved to pull out of the event_push_actions table instead
 # of listening on the event stream: this would avoid them having to run the
 # rules again.
@@ -57,6 +69,8 @@ class Pusher(object):
         self.alive = True
         self.badge = None
 
+        self.name = "Pusher-%d" % (_get_next_id(),)
+
         # The last value of last_active_time that we saw
         self.last_last_active_time = 0
         self.has_unread = True
@@ -86,38 +100,46 @@ class Pusher(object):
 
     @defer.inlineCallbacks
     def start(self):
-        if not self.last_token:
-            # First-time setup: get a token to start from (we can't
-            # just start from no token, ie. 'now'
-            # because we need the result to be reproduceable in case
-            # we fail to dispatch the push)
-            config = PaginationConfig(from_token=None, limit='1')
-            chunk = yield self.evStreamHandler.get_stream(
-                self.user_id, config, timeout=0, affect_presence=False
-            )
-            self.last_token = chunk['end']
-            self.store.update_pusher_last_token(
-                self.app_id, self.pushkey, self.user_id, self.last_token
-            )
-            logger.info("Pusher %s for user %s starting from token %s",
-                        self.pushkey, self.user_id, self.last_token)
-
-        wait = 0
-        while self.alive:
-            try:
-                if wait > 0:
-                    yield synapse.util.async.sleep(wait)
-                yield self.get_and_dispatch()
-                wait = 0
-            except:
-                if wait == 0:
-                    wait = 1
-                else:
-                    wait = min(wait * 2, 1800)
-                logger.exception(
-                    "Exception in pusher loop for pushkey %s. Pausing for %ds",
-                    self.pushkey, wait
+        with LoggingContext(self.name):
+            if not self.last_token:
+                # First-time setup: get a token to start from (we can't
+                # just start from no token, ie. 'now'
+                # because we need the result to be reproduceable in case
+                # we fail to dispatch the push)
+                config = PaginationConfig(from_token=None, limit='1')
+                chunk = yield self.evStreamHandler.get_stream(
+                    self.user_id, config, timeout=0, affect_presence=False
                 )
+                self.last_token = chunk['end']
+                self.store.update_pusher_last_token(
+                    self.app_id, self.pushkey, self.user_id, self.last_token
+                )
+                logger.info("New pusher %s for user %s starting from token %s",
+                            self.pushkey, self.user_id, self.last_token)
+
+            else:
+                logger.info(
+                    "Old pusher %s for user %s starting",
+                    self.pushkey, self.user_id,
+                )
+
+            wait = 0
+            while self.alive:
+                try:
+                    if wait > 0:
+                        yield synapse.util.async.sleep(wait)
+                    with Measure(self.clock, "push"):
+                        yield self.get_and_dispatch()
+                    wait = 0
+                except:
+                    if wait == 0:
+                        wait = 1
+                    else:
+                        wait = min(wait * 2, 1800)
+                    logger.exception(
+                        "Exception in pusher loop for pushkey %s. Pausing for %ds",
+                        self.pushkey, wait
+                    )
 
     @defer.inlineCallbacks
     def get_and_dispatch(self):
diff --git a/synapse/util/metrics.py b/synapse/util/metrics.py
new file mode 100644
index 0000000000..daf6087fe0
--- /dev/null
+++ b/synapse/util/metrics.py
@@ -0,0 +1,86 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+from synapse.util.logcontext import LoggingContext
+import synapse.metrics
+
+import logging
+
+
+logger = logging.getLogger(__name__)
+
+
+metrics = synapse.metrics.get_metrics_for(__name__)
+
+block_timer = metrics.register_distribution(
+    "block_timer",
+    labels=["block_name"]
+)
+
+block_ru_utime = metrics.register_distribution(
+    "block_ru_utime", labels=["block_name"]
+)
+
+block_ru_stime = metrics.register_distribution(
+    "block_ru_stime", labels=["block_name"]
+)
+
+block_db_txn_count = metrics.register_distribution(
+    "block_db_txn_count", labels=["block_name"]
+)
+
+block_db_txn_duration = metrics.register_distribution(
+    "block_db_txn_duration", labels=["block_name"]
+)
+
+
+class Measure(object):
+    __slots__ = ["clock", "name", "start_context", "start"]
+
+    def __init__(self, clock, name):
+        self.clock = clock
+        self.name = name
+        self.start_context = None
+        self.start = None
+
+    def __enter__(self):
+        self.start = self.clock.time_msec()
+        self.start_context = LoggingContext.current_context()
+
+    def __exit__(self, exc_type, exc_val, exc_tb):
+        if exc_type is not None:
+            return
+
+        duration = self.clock.time_msec() - self.start
+        block_timer.inc_by(duration, self.name)
+
+        context = LoggingContext.current_context()
+        if not context:
+            return
+
+        if context != self.start_context:
+            logger.warn(
+                "Context have unexpectedly changed %r, %r",
+                context, self.start_context
+            )
+            return
+
+        ru_utime, ru_stime = context.get_resource_usage()
+
+        block_ru_utime.inc_by(ru_utime, self.name)
+        block_ru_stime.inc_by(ru_stime, self.name)
+        block_db_txn_count.inc_by(context.db_txn_count, self.name)
+        block_db_txn_duration.inc_by(context.db_txn_duration, self.name)