From 82d2168a15741ed4546c12c06d797627469fb684 Mon Sep 17 00:00:00 2001 From: Erik Johnston Date: Mon, 1 Nov 2021 11:21:36 +0000 Subject: [PATCH] Add metrics to the threadpools (#11178) --- changelog.d/11178.feature | 1 + synapse/app/_base.py | 5 +++++ synapse/metrics/__init__.py | 37 +++++++++++++++++++++++++++++++++++++ synapse/storage/database.py | 7 ++++++- 4 files changed, 49 insertions(+), 1 deletion(-) create mode 100644 changelog.d/11178.feature diff --git a/changelog.d/11178.feature b/changelog.d/11178.feature new file mode 100644 index 000000000..10b1cdffd --- /dev/null +++ b/changelog.d/11178.feature @@ -0,0 +1 @@ +Add metrics for thread pool usage. diff --git a/synapse/app/_base.py b/synapse/app/_base.py index f4c3f867a..f2c1028b5 100644 --- a/synapse/app/_base.py +++ b/synapse/app/_base.py @@ -45,6 +45,7 @@ from synapse.events.spamcheck import load_legacy_spam_checkers from synapse.events.third_party_rules import load_legacy_third_party_event_rules from synapse.handlers.auth import load_legacy_password_auth_providers from synapse.logging.context import PreserveLoggingContext +from synapse.metrics import register_threadpool from synapse.metrics.background_process_metrics import wrap_as_background_process from synapse.metrics.jemalloc import setup_jemalloc_stats from synapse.util.caches.lrucache import setup_expire_lru_cache_entries @@ -351,6 +352,10 @@ async def start(hs: "HomeServer"): GAIResolver(reactor, getThreadPool=lambda: resolver_threadpool) ) + # Register the threadpools with our metrics. + register_threadpool("default", reactor.getThreadPool()) + register_threadpool("gai_resolver", resolver_threadpool) + # Set up the SIGHUP machinery. if hasattr(signal, "SIGHUP"): diff --git a/synapse/metrics/__init__.py b/synapse/metrics/__init__.py index e902109af..91ee5c819 100644 --- a/synapse/metrics/__init__.py +++ b/synapse/metrics/__init__.py @@ -32,6 +32,7 @@ from prometheus_client.core import ( ) from twisted.internet import reactor +from twisted.python.threadpool import ThreadPool import synapse from synapse.metrics._exposition import ( @@ -526,6 +527,42 @@ threepid_send_requests = Histogram( labelnames=("type", "reason"), ) +threadpool_total_threads = Gauge( + "synapse_threadpool_total_threads", + "Total number of threads currently in the threadpool", + ["name"], +) + +threadpool_total_working_threads = Gauge( + "synapse_threadpool_working_threads", + "Number of threads currently working in the threadpool", + ["name"], +) + +threadpool_total_min_threads = Gauge( + "synapse_threadpool_min_threads", + "Minimum number of threads configured in the threadpool", + ["name"], +) + +threadpool_total_max_threads = Gauge( + "synapse_threadpool_max_threads", + "Maximum number of threads configured in the threadpool", + ["name"], +) + + +def register_threadpool(name: str, threadpool: ThreadPool) -> None: + """Add metrics for the threadpool.""" + + threadpool_total_min_threads.labels(name).set(threadpool.min) + threadpool_total_max_threads.labels(name).set(threadpool.max) + + threadpool_total_threads.labels(name).set_function(lambda: len(threadpool.threads)) + threadpool_total_working_threads.labels(name).set_function( + lambda: len(threadpool.working) + ) + class ReactorLastSeenMetric: def collect(self): diff --git a/synapse/storage/database.py b/synapse/storage/database.py index fa4e89d35..5c71e2751 100644 --- a/synapse/storage/database.py +++ b/synapse/storage/database.py @@ -48,6 +48,7 @@ from synapse.logging.context import ( current_context, make_deferred_yieldable, ) +from synapse.metrics import register_threadpool from synapse.metrics.background_process_metrics import run_as_background_process from synapse.storage.background_updates import BackgroundUpdater from synapse.storage.engines import BaseDatabaseEngine, PostgresEngine, Sqlite3Engine @@ -104,13 +105,17 @@ def make_pool( LoggingDatabaseConnection(conn, engine, "on_new_connection") ) - return adbapi.ConnectionPool( + connection_pool = adbapi.ConnectionPool( db_config.config["name"], cp_reactor=reactor, cp_openfun=_on_new_connection, **db_args, ) + register_threadpool(f"database-{db_config.name}", connection_pool.threadpool) + + return connection_pool + def make_conn( db_config: DatabaseConnectionConfig,