From 159434a13301f7838d2ca8d26e16a856216a318a Mon Sep 17 00:00:00 2001
From: "Paul \"LeoNerd\" Evans" <paul@matrix.org>
Date: Fri, 28 Oct 2016 13:58:27 +0100
Subject: [PATCH 1/2] Remove long-deprecated instructions about promethesus
 console; also fix for modern config file format

---
 docs/metrics-howto.rst | 39 +++++++--------------------------------
 1 file changed, 7 insertions(+), 32 deletions(-)

diff --git a/docs/metrics-howto.rst b/docs/metrics-howto.rst
index c1f5ae217..9f5f1767e 100644
--- a/docs/metrics-howto.rst
+++ b/docs/metrics-howto.rst
@@ -15,36 +15,11 @@ How to monitor Synapse metrics using Prometheus
 
   Restart synapse
 
-3: Check out synapse-prometheus-config
-  https://github.com/matrix-org/synapse-prometheus-config
+3: Add a prometheus target for synapse. It needs to set the ``metrics_path``
+   to a non-default value::
 
-4: Add ``synapse.html`` and ``synapse.rules``
-  The ``.html`` file needs to appear in prometheus's ``consoles`` directory,
-  and the ``.rules`` file needs to be invoked somewhere in the main config
-  file. A symlink to each from the git checkout into the prometheus directory
-  might be easiest to ensure ``git pull`` keeps it updated.
-
-5: Add a prometheus target for synapse
-  This is easiest if prometheus runs on the same machine as synapse, as it can
-  then just use localhost::
-
-    global: {
-      rule_file: "synapse.rules"
-    }
-
-    job: {
-      name: "synapse"
-
-      target_group: {
-        target: "http://localhost:9092/"
-      }
-    }
-
-6: Start prometheus::
-
-   ./prometheus -config.file=prometheus.conf
-
-7: Wait a few seconds for it to start and perform the first scrape,
-   then visit the console:
-
-    http://server-where-prometheus-runs:9090/consoles/synapse.html
+    - job_name: "synapse"
+      metrics_path: "/_synapse/metrics"
+      static_configs:
+        - targets:
+            "my.server.here:9092"

From 1d4d518b50edec020faad41cc857edbf75b47eda Mon Sep 17 00:00:00 2001
From: "Paul \"LeoNerd\" Evans" <paul@matrix.org>
Date: Mon, 31 Oct 2016 15:06:52 +0000
Subject: [PATCH 2/2] Add details of renamed metrics

---
 docs/metrics-howto.rst | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/docs/metrics-howto.rst b/docs/metrics-howto.rst
index 9f5f1767e..7aa4757a3 100644
--- a/docs/metrics-howto.rst
+++ b/docs/metrics-howto.rst
@@ -23,3 +23,37 @@ How to monitor Synapse metrics using Prometheus
       static_configs:
         - targets:
             "my.server.here:9092"
+
+Standard Metric Names
+---------------------
+
+As of synapse version 0.18.2, the format of the process-wide metrics has been
+changed to fit prometheus standard naming conventions. Additionally the units
+have been changed to seconds, from miliseconds.
+
+================================== =============================
+New name                           Old name
+---------------------------------- -----------------------------
+process_cpu_user_seconds_total     process_resource_utime / 1000
+process_cpu_system_seconds_total   process_resource_stime / 1000
+process_open_fds (no 'type' label) process_fds
+================================== =============================
+
+The python-specific counts of garbage collector performance have been renamed.
+
+=========================== ======================
+New name                    Old name
+--------------------------- ----------------------
+python_gc_time              reactor_gc_time      
+python_gc_unreachable_total reactor_gc_unreachable
+python_gc_counts            reactor_gc_counts
+=========================== ======================
+
+The twisted-specific reactor metrics have been renamed.
+
+==================================== =================
+New name                             Old name
+------------------------------------ -----------------
+python_twisted_reactor_pending_calls reactor_tick_time
+python_twisted_reactor_tick_time     reactor_tick_time
+==================================== =================