Adds new metrics for unicorn monitoring

This adds new metrics for monitoring unicorn. These metrics include
process_cpu_seconds_total, process_start_time_seconds, process_max_fds,
and unicorn_workers.

1 files changed, 28 insertions, 8 deletions

diff --git a/lib/gitlab/metrics/samplers/unicorn_sampler.rb b/lib/gitlab/metrics/samplers/unicorn_sampler.rb
index bec64e864b3..16a2ee9b9be 100644
--- a/lib/gitlab/metrics/samplers/unicorn_sampler.rb
+++ b/lib/gitlab/metrics/samplers/unicorn_sampler.rb
@@ -8,12 +8,19 @@ module Gitlab
           super(interval)
         end
 
-        def unicorn_active_connections
-          @unicorn_active_connections ||= ::Gitlab::Metrics.gauge(:unicorn_active_connections, 'Unicorn active connections', {}, :max)
+        def metrics
+          @metrics ||= init_metrics
         end
 
-        def unicorn_queued_connections
-          @unicorn_queued_connections ||= ::Gitlab::Metrics.gauge(:unicorn_queued_connections, 'Unicorn queued connections', {}, :max)
+        def init_metrics
+          {
+            unicorn_active_connections: ::Gitlab::Metrics.gauge(:unicorn_active_connections, 'Unicorn active connections', {}, :max),
+            unicorn_queued_connections: ::Gitlab::Metrics.gauge(:unicorn_queued_connections, 'Unicorn queued connections', {}, :max),
+            unicorn_workers:            ::Gitlab::Metrics.gauge(:unicorn_workers, 'Unicorn workers'),
+            process_cpu_seconds_total:  ::Gitlab::Metrics.gauge(:process_cpu_seconds_total, 'Process CPU seconds total'),
+            process_max_fds:            ::Gitlab::Metrics.gauge(:process_max_fds, 'Process max fds'),
+            process_start_time_seconds: ::Gitlab::Metrics.gauge(:process_start_time_seconds, 'Process start time seconds')
+          }
         end
 
         def enabled?
@@ -23,14 +30,19 @@ module Gitlab
 
         def sample
           Raindrops::Linux.tcp_listener_stats(tcp_listeners).each do |addr, stats|
-            unicorn_active_connections.set({ socket_type: 'tcp', socket_address: addr }, stats.active)
-            unicorn_queued_connections.set({ socket_type: 'tcp', socket_address: addr }, stats.queued)
+            metrics[:unicorn_active_connections].set({ socket_type: 'tcp', socket_address: addr }, stats.active)
+            metrics[:unicorn_queued_connections].set({ socket_type: 'tcp', socket_address: addr }, stats.queued)
           end
 
           Raindrops::Linux.unix_listener_stats(unix_listeners).each do |addr, stats|
-            unicorn_active_connections.set({ socket_type: 'unix', socket_address: addr }, stats.active)
-            unicorn_queued_connections.set({ socket_type: 'unix', socket_address: addr }, stats.queued)
+            metrics[:unicorn_active_connections].set({ socket_type: 'unix', socket_address: addr }, stats.active)
+            metrics[:unicorn_queued_connections].set({ socket_type: 'unix', socket_address: addr }, stats.queued)
           end
+
+          metrics[:process_cpu_seconds_total].set({ pid: nil }, ::Gitlab::Metrics::System.cpu_time)
+          metrics[:process_start_time_seconds].set({ pid: nil }, ::Gitlab::Metrics::System.process_start_time)
+          metrics[:process_max_fds].set({ pid: nil }, ::Gitlab::Metrics::System.max_open_file_descriptors)
+          metrics[:unicorn_workers].set({}, unicorn_workers_count)
         end
 
         private
@@ -39,6 +51,10 @@ module Gitlab
           @tcp_listeners ||= Unicorn.listener_names.grep(%r{\A[^/]+:\d+\z})
         end
 
+        def pid
+          @pid ||= Process.pid
+        end
+
         def unix_listeners
           @unix_listeners ||= Unicorn.listener_names - tcp_listeners
         end
@@ -46,6 +62,10 @@ module Gitlab
         def unicorn_with_listeners?
           defined?(Unicorn) && Unicorn.listener_names.any?
         end
+
+        def unicorn_workers_count
+          Sys::ProcTable.ps.select {|p| p.cmdline.match(/unicorn_rails worker/)}.count
+        end
       end
     end
   end