Add latest changes from gitlab-org/gitlab@15-9-stable-eev15.9.0-rc42

1 files changed, 24 insertions, 0 deletions

diff --git a/lib/gitlab/memory/watchdog/handlers/null_handler.rb b/lib/gitlab/memory/watchdog/handlers/null_handler.rb
new file mode 100644
index 00000000000..127001003ce
--- /dev/null
+++ b/lib/gitlab/memory/watchdog/handlers/null_handler.rb
@@ -0,0 +1,24 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module Memory
+    class Watchdog
+      module Handlers
+        # This handler does nothing. It returns `false` to indicate to the
+        # caller that the situation has not been dealt with so it will
+        # receive calls repeatedly if fragmentation remains high.
+        #
+        # This is useful for "dress rehearsals" in production since it allows
+        # us to observe how frequently the handler is invoked before taking action.
+        class NullHandler
+          include Singleton
+
+          def call
+            # NOP
+            false
+          end
+        end
+      end
+    end
+  end
+end