From 9eea4646be5eef1e2b24e3b0bb0fc94999c2250c Mon Sep 17 00:00:00 2001
From: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>
Date: Thu, 3 Jun 2021 16:31:56 +0100
Subject: Add OpenTracing for database activity. (#10113)

This adds quite a lot of OpenTracing decoration for database activity. Specifically it adds tracing at four different levels:

 * emit a span for each "interaction" - ie, the top level database function that we tend to call "transaction", but isn't really, because it can end up as multiple transactions.
 * emit a span while we hold a database connection open
 * emit a span for each database transaction - actual actual transaction.
 * emit a span for each database query.

I'm aware this might be quite a lot of overhead, but even just running it on a local Synapse it looks really interesting, and I hope the overhead can be offset just by turning down the sampling frequency and finding other ways of tracing requests of interest (eg, the `force_tracing_for_users` setting).
---
 synapse/logging/opentracing.py | 6 ++++++
 1 file changed, 6 insertions(+)

(limited to 'synapse/logging/opentracing.py')

diff --git a/synapse/logging/opentracing.py b/synapse/logging/opentracing.py
index f64845b80c..68f0c00151 100644
--- a/synapse/logging/opentracing.py
+++ b/synapse/logging/opentracing.py
@@ -271,6 +271,12 @@ class SynapseTags:
     # HTTP request tag (used to distinguish full vs incremental syncs, etc)
     REQUEST_TAG = "request_tag"
 
+    # Text description of a database transaction
+    DB_TXN_DESC = "db.txn_desc"
+
+    # Uniqueish ID of a database transaction
+    DB_TXN_ID = "db.txn_id"
+
 
 # Block everything by default
 # A regex which matches the server_names to expose traces for.
-- 
cgit 1.5.1


From d8be7d493d7a91a55ee37a7931157d4557a508fb Mon Sep 17 00:00:00 2001
From: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>
Date: Fri, 4 Jun 2021 09:25:33 +0100
Subject: Enable Prometheus metrics for the jaeger client library (#10112)

---
 changelog.d/10112.misc         | 1 +
 mypy.ini                       | 2 +-
 synapse/logging/opentracing.py | 3 +++
 3 files changed, 5 insertions(+), 1 deletion(-)
 create mode 100644 changelog.d/10112.misc

(limited to 'synapse/logging/opentracing.py')

diff --git a/changelog.d/10112.misc b/changelog.d/10112.misc
new file mode 100644
index 0000000000..40af09760c
--- /dev/null
+++ b/changelog.d/10112.misc
@@ -0,0 +1 @@
+Enable Prometheus metrics for the jaeger client library.
diff --git a/mypy.ini b/mypy.ini
index 062872020e..8ba1b96311 100644
--- a/mypy.ini
+++ b/mypy.ini
@@ -130,7 +130,7 @@ ignore_missing_imports = True
 [mypy-canonicaljson]
 ignore_missing_imports = True
 
-[mypy-jaeger_client]
+[mypy-jaeger_client.*]
 ignore_missing_imports = True
 
 [mypy-jsonschema]
diff --git a/synapse/logging/opentracing.py b/synapse/logging/opentracing.py
index 68f0c00151..26c8ffe780 100644
--- a/synapse/logging/opentracing.py
+++ b/synapse/logging/opentracing.py
@@ -362,10 +362,13 @@ def init_tracer(hs: "HomeServer"):
 
     set_homeserver_whitelist(hs.config.opentracer_whitelist)
 
+    from jaeger_client.metrics.prometheus import PrometheusMetricsFactory
+
     config = JaegerConfig(
         config=hs.config.jaeger_config,
         service_name="{} {}".format(hs.config.server_name, hs.get_instance_name()),
         scope_manager=LogContextScopeManager(hs.config),
+        metrics_factory=PrometheusMetricsFactory(),
     )
 
     # If we have the rust jaeger reporter available let's use that.
-- 
cgit 1.5.1