diff --git a/CONTRIBUTORS.md b/CONTRIBUTORS.md
index 74ea48ffa..62edc6672 100644
--- a/CONTRIBUTORS.md
+++ b/CONTRIBUTORS.md
@@ -34,6 +34,7 @@ Contributors
 * Nick Fagerlund <nick.fagerlund@gmail.com>
 * Nick Lewis <nick@puppetlabs.com>
 * Nigel Kersten <nigel@puppetlabs.com>
+* Pascal Vibet <p.vibet@gmail.com>
 * Patrick Carlisle <patrick@puppetlabs.com>
 * Paul Berry <paul@puppetlabs.com>
 * Peter Meier <peter.meier@immerda.ch>
diff --git a/README.markdown b/README.markdown
index 5b85bb698..981135081 100644
--- a/README.markdown
+++ b/README.markdown
@@ -73,7 +73,7 @@ bundle install --deployment
 ````
 * You need to create a secret for production and either set it via environment variable:
   `export SECRET_KEY_BASE=$(bundle exec rails secret)`
-  or follow the instructions in config/secrets.yml to setup an encrypted secret. 
+  or follow the instructions in config/secrets.yml to setup an encrypted secret.
 * Setup database and pre-compile assets
 ````
 RAILS_ENV=production bundle exec rake db:setup && \
@@ -96,9 +96,17 @@ precompile assets for production using:
 
  * `SECRET_KEY_BASE=none RAILS_ENV=production bundle exec rails assets:precompile`
 
+Dashboard will keep all reports in the database. If your infrastructure is big the database will
+eventually become very large (more than 50GB). To periodically purge old reports (~ once per day)
+and optimize the database tables (~ once per month) it is recommended to run the following tasks
+periodically:
+
+ * `SECRET_KEY_BASE=none RAILS_ENV=production bundle exec rails reports:prune upto=20 unit=day`
+ * `SECRET_KEY_BASE=none RAILS_ENV=production bundle exec rails db:raw:optimize`
+
 Contributing
 ------------
 
-To contribute to this project, please read [CONTRIBUTING](CONTRIBUTING.md).  
-A list of contributors is found in [CONTRIBUTORS](CONTRIBUTORS.md). Thanks!  
+To contribute to this project, please read [CONTRIBUTING](CONTRIBUTING.md).
+A list of contributors is found in [CONTRIBUTORS](CONTRIBUTORS.md). Thanks!
 This project uses the [Silk icons](http://www.famfamfam.com/lab/icons/silk/) by Mark James.  Thank you!
diff --git a/lib/tasks/db_raw.rake b/lib/tasks/db_raw.rake
index 3b65df55b..9daa16393 100644
--- a/lib/tasks/db_raw.rake
+++ b/lib/tasks/db_raw.rake
@@ -57,10 +57,16 @@ namespace :db do
       case adapter
       when 'mysql', 'mysql2'
         puts "Optimizing tables, this may take a while:"
-        for table in ActiveRecord::Base.connection.select_values('SHOW TABLES').sort
+        for table in ActiveRecord::Base.connection.tables.sort
           puts "* #{table}"
           ActiveRecord::Base.connection.execute("OPTIMIZE TABLE #{table}")
         end
+      when 'postgresql'
+        puts "Optimizing tables, this may take a while:"
+        for table in ActiveRecord::Base.connection.tables.sort
+          puts "* #{table}"
+          ActiveRecord::Base.connection.execute("VACUUM FULL ANALYZE #{table}")
+        end
       else
         raise "Don't know how to optimize for database engine: #{adapter}"
       end