Google's App Engine platform has been available for developers to build upon since last April, and in that time has been free to all, up to certain resource limits. Many have taken advantage of that capability to build thousands of apps including some now in our directory like the iTunes clone The Cloud Player and the Yahoo BOSS search mashup 4hoursearch. But the most common request from App Engine developers has been the ability to go beyond the initial resource limits. As of today, Google has lifted those limits and will let apps scale beyond those early free quotas.
This announcement means that developers who need more bandwidth, CPU, or storage can pay Google for them. The free resources will remain but with the levels changed somewhat. Over the next ninety days the free storage quota will be doubled to 1 GB, and other free resource quotas reduced, to a level that Google says will make "reasonably efficient applications serving around 5 million page views per month" remain completely free.
Beyond that the announcement states the pricing as:
- $0.10 per CPU core hour. This covers the actual CPU time an application uses to process a given request, as well that for any Datastore usage.
- $0.10 per GB bandwidth incoming, $0.12 per GB bandwidth outgoing. This covers traffic directly to/from users, traffic between the app and any external servers accessed using the URLFetch API, and data sent via the Email API.
- $0.15 per GB of data stored by the application per month.
- $0.0001 per email recipient for emails sent by the application
For more specifics, Google has setup a Purchasing Additional Quota that quotas, billing and "daily budgets".
Frederic Lardenois of ReadWriteWeb notes that the pricing seems to be "slightly cheaper and less complicated than Amazon's pricing schemes for using its EC2 and S3 service," while reminding us that the App Engine technology is limited to Python environments for now (as opposed to Amazon's EC2 for example - see our EC2 source code matches for PHP, Java, Python, Ruby, and Perl). It's widely expected that Google will add support for additional languages before long.
Having predictable pricing models and recognized service levels can only make cloud computing more appealing for enterprising developers by letting them focus on their applications and not their infrastructure.