added the ability to limit memory consumption of code submissions executed using Docker

db/migrate/20150317083739_add_memory_limit_to_execution_environments.rb

@@ -0,0 +1,11 @@
+class AddMemoryLimitToExecutionEnvironments < ActiveRecord::Migration
+  def change
+    add_column :execution_environments, :memory_limit, :integer
+
+    reversible do |direction|
+      direction.up do
+        ExecutionEnvironment.update_all(memory_limit: DockerClient::DEFAULT_MEMORY_LIMIT)
+      end
+    end
+  end
+end

db/schema.rb

@@ -11,7 +11,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20150310150712) do
+ActiveRecord::Schema.define(version: 20150317083739) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -46,6 +46,7 @@ ActiveRecord::Schema.define(version: 20150310150712) do
     t.string   "user_type"
     t.integer  "pool_size"
     t.integer  "file_type_id"
+    t.integer  "memory_limit"
   end
 
   create_table "exercises", force: true do |t|