From 2b7c180879e5d62145feed88375ba55f18fc2ae5 Mon Sep 17 00:00:00 2001 From: Erik Johnston Date: Mon, 26 Oct 2020 09:30:19 +0000 Subject: Start fewer opentracing spans (#8640) #8567 started a span for every background process. This is good as it means all Synapse code that gets run should be in a span (unless in the sentinel logging context), but it means we generate about 15x the number of spans as we did previously. This PR attempts to reduce that number by a) not starting one for send commands to Redis, and b) deferring starting background processes until after we're sure they're necessary. I don't really know how much this will help. --- synapse/metrics/background_process_metrics.py | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) (limited to 'synapse/metrics') diff --git a/synapse/metrics/background_process_metrics.py b/synapse/metrics/background_process_metrics.py index 08fbf78eee..658f6ecd72 100644 --- a/synapse/metrics/background_process_metrics.py +++ b/synapse/metrics/background_process_metrics.py @@ -24,7 +24,7 @@ from prometheus_client.core import REGISTRY, Counter, Gauge from twisted.internet import defer from synapse.logging.context import LoggingContext, PreserveLoggingContext -from synapse.logging.opentracing import start_active_span +from synapse.logging.opentracing import noop_context_manager, start_active_span if TYPE_CHECKING: import resource @@ -167,7 +167,7 @@ class _BackgroundProcess: ) -def run_as_background_process(desc: str, func, *args, **kwargs): +def run_as_background_process(desc: str, func, *args, bg_start_span=True, **kwargs): """Run the given function in its own logcontext, with resource metrics This should be used to wrap processes which are fired off to run in the @@ -181,6 +181,9 @@ def run_as_background_process(desc: str, func, *args, **kwargs): Args: desc: a description for this background process type func: a function, which may return a Deferred or a coroutine + bg_start_span: Whether to start an opentracing span. Defaults to True. + Should only be disabled for processes that will not log to or tag + a span. args: positional args for func kwargs: keyword args for func @@ -199,7 +202,10 @@ def run_as_background_process(desc: str, func, *args, **kwargs): with BackgroundProcessLoggingContext(desc) as context: context.request = "%s-%i" % (desc, count) try: - with start_active_span(desc, tags={"request_id": context.request}): + ctx = noop_context_manager() + if bg_start_span: + ctx = start_active_span(desc, tags={"request_id": context.request}) + with ctx: result = func(*args, **kwargs) if inspect.isawaitable(result): -- cgit 1.4.1