From 020377a5504602cb5d2ce555c77bd18eefc87635 Mon Sep 17 00:00:00 2001 From: Erik Johnston Date: Tue, 22 May 2018 11:16:07 +0100 Subject: [PATCH 1/2] Fix logcontext resource usage tracking --- synapse/util/logcontext.py | 38 +++++++++++++++++++++++++++----------- 1 file changed, 27 insertions(+), 11 deletions(-) diff --git a/synapse/util/logcontext.py b/synapse/util/logcontext.py index eab9d57650..0bbda1dcaf 100644 --- a/synapse/util/logcontext.py +++ b/synapse/util/logcontext.py @@ -60,7 +60,7 @@ class LoggingContext(object): __slots__ = [ "previous_context", "name", "ru_stime", "ru_utime", "db_txn_count", "db_txn_duration_ms", "db_sched_duration_ms", - "usage_start", "usage_end", + "usage_start", "main_thread", "alive", "request", "tag", ] @@ -109,8 +109,10 @@ class LoggingContext(object): # ms spent waiting for db txns to be scheduled self.db_sched_duration_ms = 0 + # If alive has the thread resource usage when the logcontext last + # became active. self.usage_start = None - self.usage_end = None + self.main_thread = threading.current_thread() self.request = None self.tag = "" @@ -159,7 +161,7 @@ class LoggingContext(object): """Restore the logging context in thread local storage to the state it was before this context was entered. Returns: - None to avoid suppressing any exeptions that were thrown. + None to avoid suppressing any exceptions that were thrown. """ current = self.set_current_context(self.previous_context) if current is not self: @@ -185,29 +187,43 @@ class LoggingContext(object): def start(self): if threading.current_thread() is not self.main_thread: + logger.warning("Started logcontext %s on different thread", self) return - if self.usage_start and self.usage_end: - self.ru_utime += self.usage_end.ru_utime - self.usage_start.ru_utime - self.ru_stime += self.usage_end.ru_stime - self.usage_start.ru_stime - self.usage_start = None - self.usage_end = None - + # If we haven't already started record the thread resource usage so + # far if not self.usage_start: self.usage_start = get_thread_resource_usage() def stop(self): if threading.current_thread() is not self.main_thread: + logger.warning("Stopped logcontext %s on different thread", self) return + # When we stop lets record the resource used since we started if self.usage_start: - self.usage_end = get_thread_resource_usage() + usage_end = get_thread_resource_usage() + + self.ru_utime += usage_end.ru_utime - self.usage_start.ru_utime + self.ru_stime += usage_end.ru_stime - self.usage_start.ru_stime + + self.usage_start = None + else: + logger.warning("Called stop on logcontext %s without calling start", self) def get_resource_usage(self): + """Get CPU time used by this logcontext so far. + + Returns: + tuple[float, float]: The user and system CPU usage in seconds + """ ru_utime = self.ru_utime ru_stime = self.ru_stime - if self.usage_start and threading.current_thread() is self.main_thread: + # If we are on the correct thread and we're currently running then we + # can include resource usage so far. + is_main_thread = threading.current_thread() is self.main_thread + if self.alive and self.usage_start and is_main_thread: current = get_thread_resource_usage() ru_utime += current.ru_utime - self.usage_start.ru_utime ru_stime += current.ru_stime - self.usage_start.ru_stime From 7948ecf2342d7053a6ff6daa01268b9331e1c569 Mon Sep 17 00:00:00 2001 From: Erik Johnston Date: Tue, 22 May 2018 11:39:43 +0100 Subject: [PATCH 2/2] Comment --- synapse/util/logcontext.py | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/synapse/util/logcontext.py b/synapse/util/logcontext.py index 0bbda1dcaf..914f616312 100644 --- a/synapse/util/logcontext.py +++ b/synapse/util/logcontext.py @@ -200,7 +200,7 @@ class LoggingContext(object): logger.warning("Stopped logcontext %s on different thread", self) return - # When we stop lets record the resource used since we started + # When we stop, let's record the resource used since we started if self.usage_start: usage_end = get_thread_resource_usage()