Merge branch '31034-cache-classes-in-ci' into 'master'

Cache classes in CI

See merge request gitlab-org/gitlab!20949

config/environments/test.rb

@@ -10,11 +10,8 @@ Rails.application.configure do
   # your test database is "scratch space" for the test suite and is wiped
   # and recreated between test runs. Don't rely on the data there!
 
-  # Enabling caching of classes slows start-up time because all controllers
-  # are loaded at initialization, but it reduces memory and load because files
-  # are not reloaded with every request. For example, caching is not necessary
-  # for loading database migrations but useful for handling Knapsack specs.
-  config.cache_classes = ENV['CACHE_CLASSES'] == 'true'
+  # Code doesn't change in CI so we don't need code-reloading
+  config.cache_classes = !!ENV['CI']
 
   # Configure static asset server for tests with Cache-Control for performance
   config.assets.compile = false if ENV['CI']

scripts/rspec_helpers.sh

@@ -40,7 +40,6 @@ function rspec_simple_job() {
   local rspec_opts="${1}"
 
   export NO_KNAPSACK="1"
-  export CACHE_CLASSES="true"
 
   scripts/gitaly-test-spawn
 
@@ -59,7 +58,6 @@ function rspec_paralellized_job() {
     spec_folder_prefix="ee/"
   fi
 
-  export CACHE_CLASSES="true"
   export KNAPSACK_LOG_LEVEL="debug"
   export KNAPSACK_REPORT_PATH="knapsack/${test_tool}_${test_level}_${database}_${CI_NODE_INDEX}_${CI_NODE_TOTAL}_report.json"