From fc8471c6d411e3fd27e73f9e408c2c1abed09a88 Mon Sep 17 00:00:00 2001
From: Sebastian Serth <Sebastian.Serth@hpi.de>
Date: Mon, 19 Apr 2021 17:19:49 +0200
Subject: [PATCH] Parallelize initial Prometheus metric collection

---
 lib/prometheus/controller.rb | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/lib/prometheus/controller.rb b/lib/prometheus/controller.rb
index 0b85beae..d467b1d4 100644
--- a/lib/prometheus/controller.rb
+++ b/lib/prometheus/controller.rb
@@ -11,8 +11,15 @@ module Prometheus
     class << self
       def initialize_metrics
         register_metrics
-        initialize_instance_count
-        initialize_rfc_metrics
+
+        Thread.new do
+          initialize_instance_count
+          initialize_rfc_metrics
+        rescue StandardError => e
+          Sentry.capture_exception(e)
+        ensure
+          ActiveRecord::Base.connection_pool.release_connection
+        end
       end
 
       def register_metrics