From 499d4a32cda7bc26d82140d84a7279372c519538 Mon Sep 17 00:00:00 2001 From: Erik Johnston Date: Mon, 17 Jun 2019 16:20:20 +0100 Subject: [PATCH] Add metrics for len of new extremities persisted. Of new events being persisted add metrics for total size of forward extremities and number of unchanged, "stale" extremities. --- synapse/storage/events.py | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) diff --git a/synapse/storage/events.py b/synapse/storage/events.py index f631fb173..f2374bc3f 100644 --- a/synapse/storage/events.py +++ b/synapse/storage/events.py @@ -24,7 +24,7 @@ from six import iteritems, text_type from six.moves import range from canonicaljson import json -from prometheus_client import Counter +from prometheus_client import Counter, Histogram from twisted.internet import defer @@ -74,6 +74,19 @@ state_delta_reuse_delta_counter = Counter( "synapse_storage_events_state_delta_reuse_delta", "" ) +# The number of forward extremities for each new event. +forward_extremities_counter = Histogram( + "synapse_storage_events_forward_extremities_persisted", "", + buckets=(1, 2, 3, 5, 7, 10, 15, 20, 50, 100, 200, 500, "+Inf") +) + +# The number of stale forward extremities for each new event. Stale extremities +# are those that were in the previous set of extremities as well as the new. +stale_forward_extremities_counter = Histogram( + "synapse_storage_events_stale_forward_extremities_persisted", "", + buckets=(0, 1, 2, 3, 5, 7, 10, 15, 20, 50, 100, 200, 500, "+Inf") +) + def encode_json(json_object): """ @@ -541,6 +554,8 @@ class EventsStore( and not event.internal_metadata.is_soft_failed() ] + latest_event_ids = set(latest_event_ids) + # start with the existing forward extremities result = set(latest_event_ids) @@ -564,6 +579,13 @@ class EventsStore( ) result.difference_update(existing_prevs) + # We only update metrics for events that change forward extremities + # (e.g. we ignore backfill/outliers/etc) + if result != latest_event_ids: + forward_extremities_counter.observe(len(result)) + stale = set(latest_event_ids) & result + stale_forward_extremities_counter.observe(len(stale)) + defer.returnValue(result) @defer.inlineCallbacks