optimize paperclip

Gemfile

@@ -20,6 +20,7 @@ gem 'fog-local', '~> 0.4', require: false
 gem 'fog-openstack', '~> 0.1', require: false
 gem 'paperclip', '~> 5.1'
 gem 'paperclip-av-transcoder', '~> 0.6'
+gem 'posix-spawn'
 
 gem 'active_model_serializers', '~> 0.10'
 gem 'addressable', '~> 2.5'

Gemfile.lock

@@ -324,6 +324,7 @@ GEM
     pghero (1.7.0)
       activerecord
     pkg-config (1.2.8)
+    posix-spawn (0.3.13)
     powerpack (0.1.1)
     pry (0.11.3)
       coderay (~> 1.1.0)
@@ -601,6 +602,7 @@ DEPENDENCIES
   pg (~> 0.20)
   pghero (~> 1.7)
   pkg-config (~> 1.2)
+  posix-spawn
   pry-rails (~> 0.3)
   puma (~> 3.10)
   pundit (~> 1.1)