Google's App Engine is growing a step more mature, with Google planning on Tuesday to begin allowing people who use the cloud-computing foundation to pay for heavy use.
When Google launched App Engine last April, it was available as a free service with caps on computing and network resource usage. Free use is still available for lower-traffic sites, but Google now lets users pay for higher access as needed.
"It's been one of our biggest developer requests," said Pete Koomen, Google App Engine product manager.
The billing feature makes Google App Engine useful for those who want to test heavy use of their applications, as long as they're willing to pay and to put up with the continued 'preview release' status. However, the service hasn't even attained beta level, much less a service-level agreement (SLA) that promises refunds if the service goes down for too long.
Google offers such an agreement for its Google Apps online tools. "It is something we are exploring [for Google App Engine]," spokesman Jon Murchinson said.
Google App Engine competes with various other cloud-computing efforts, including Amazon's lower-level suite of web-services components, but mostly with the alternative of hosting applications on one's own equipment. Amazon Web Services also uses a pay-as-you-go pricing model.
According to Google's description of how the billing will work, each CPU core hour costs 10 cents. This covers the actual CPU time an application uses to process a given request.
Each incoming gigabyte of bandwidth costs 10 cents, and each outgoing gigabyte costs 12 cents. This covers traffic directly to or from users, traffic between the app and any external servers accessed using the URLFetch API, and data sent via the Email API. Data stored by the application per month costs 15 cents per gigabyte, and there is a charge of $0.0001 per email recipient for emails sent by the application.
Koomen would not comment on the matter, so users will have to decide for themselves whether Google is trying to set prices low to attract users; set them at a medium level to cover expenses; or set them high to generate revenue during Google's new era of financial discipline.
App Engine is designed to run web applications written in the Python programming language, though Google plans to add other language support in the future. One of its chief selling points is that it is built on Google's computing infrastructure, letting applications rapidly scale if demand spikes, without the organisation running the application having to summon a large number of new servers and network capacity.
