Change effective on 17 August 2015
Recently, we updated Performance dynos to 14GB. Today, we are renaming this dyno type to Performance-L.
In addition, we are pleased to announce the Performance-M dyno, an entirely new dyno and smaller sibling of the Performance-L dyno. This new dyno has 2.5GB of memory, 2 vCPUs, and are dedicated.
The full lineup of Professional dynos are:
For more information, see the Heroku Dyno Types Dev Center article.