Merge branch '29010-perf-bar' into 'master'

Add an optional performance bar to view performance metrics for the current page

Closes #29010

See merge request !11439

3 files changed, 68 insertions, 0 deletions

diff --git a/lib/gitlab/performance_bar.rb b/lib/gitlab/performance_bar.rb
new file mode 100644
index 00000000000..163a40ad306
--- /dev/null
+++ b/lib/gitlab/performance_bar.rb
@@ -0,0 +1,7 @@
+module Gitlab
+  module PerformanceBar
+    def self.enabled?
+      Feature.enabled?('gitlab_performance_bar')
+    end
+  end
+end
diff --git a/lib/gitlab/performance_bar/peek_performance_bar_with_rack_body.rb b/lib/gitlab/performance_bar/peek_performance_bar_with_rack_body.rb
new file mode 100644
index 00000000000..d939a6ea18d
--- /dev/null
+++ b/lib/gitlab/performance_bar/peek_performance_bar_with_rack_body.rb
@@ -0,0 +1,22 @@
+# This solves a bug with a X-Senfile header that wouldn't be set properly, see
+# https://github.com/peek/peek-performance_bar/pull/27
+module Gitlab
+  module PerformanceBar
+    module PeekPerformanceBarWithRackBody
+      def call(env)
+        @env = env
+        reset_stats
+
+        @total_requests += 1
+        first_request if @total_requests == 1
+
+        env['process.request_start'] = @start.to_f
+        env['process.total_requests'] = total_requests
+
+        status, headers, body = @app.call(env)
+        body = Rack::BodyProxy.new(body) { record_request }
+        [status, headers, body]
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/performance_bar/peek_query_tracker.rb b/lib/gitlab/performance_bar/peek_query_tracker.rb
new file mode 100644
index 00000000000..7ab80f5ee0f
--- /dev/null
+++ b/lib/gitlab/performance_bar/peek_query_tracker.rb
@@ -0,0 +1,39 @@
+# Inspired by https://github.com/peek/peek-pg/blob/master/lib/peek/views/pg.rb
+module Gitlab
+  module PerformanceBar
+    module PeekQueryTracker
+      def sorted_queries
+        PEEK_DB_CLIENT.query_details.
+          sort { |a, b| b[:duration] <=> a[:duration] }
+      end
+
+      def results
+        super.merge(queries: sorted_queries)
+      end
+
+      private
+
+      def setup_subscribers
+        super
+
+        # Reset each counter when a new request starts
+        before_request do
+          PEEK_DB_CLIENT.query_details = []
+        end
+
+        subscribe('sql.active_record') do |_, start, finish, _, data|
+          if RequestStore.active? && RequestStore.store[:peek_enabled]
+            track_query(data[:sql].strip, data[:binds], start, finish)
+          end
+        end
+      end
+
+      def track_query(raw_query, bindings, start, finish)
+        query = Gitlab::Sherlock::Query.new(raw_query, start, finish)
+        query_info = { duration: '%.3f' % query.duration, sql: query.formatted_query }
+
+        PEEK_DB_CLIENT.query_details << query_info
+      end
+    end
+  end
+end