Merge branch 'push-memory-limits' into 'master'

Increase unicorn memory limits to 400-650

Just that, following what we did in production.

It doesn't actually changes the memory graph on the workers at all, just lets the workers to do some work before they are killed.

![worker-memory](/uploads/985df04ec5284ee04ccdf74fe83b8cd2/worker-memory.png)

From issue https://gitlab.com/gitlab-com/infrastructure/issues/19

See merge request !26

files/gitlab-config-template/gitlab.rb.template

@@ -414,8 +414,8 @@ external_url 'GENERATED_EXTERNAL_URL'
 ## Only change these settings if you understand well what they mean
 ## see https://about.gitlab.com/2015/06/05/how-gitlab-uses-unicorn-and-unicorn-worker-killer/
 ## and https://github.com/kzk/unicorn-worker-killer
-# unicorn['worker_memory_limit_min'] = "300 * 1 << 20"
-# unicorn['worker_memory_limit_max'] = "350 * 1 << 20"
+# unicorn['worker_memory_limit_min'] = "400 * 1 << 20"
+# unicorn['worker_memory_limit_max'] = "650 * 1 << 20"
 ##################

files/gitlab-cookbooks/gitlab/attributes/default.rb

@@ -283,8 +283,8 @@ default['gitlab']['unicorn']['tcp_nopush'] = true
 default['gitlab']['unicorn']['backlog_socket'] = 1024
 default['gitlab']['unicorn']['somaxconn'] = 1024
 default['gitlab']['unicorn']['worker_timeout'] = 60
-default['gitlab']['unicorn']['worker_memory_limit_min'] = "300 * 1 << 20"
-default['gitlab']['unicorn']['worker_memory_limit_max'] = "350 * 1 << 20"
+default['gitlab']['unicorn']['worker_memory_limit_min'] = "400 * 1 << 20"
+default['gitlab']['unicorn']['worker_memory_limit_max'] = "650 * 1 << 20"
 ####
 # Sidekiq