Towards Automated Cloud Application Placement

Posted by Charles Loomis on 5 March 2016

By using portable cloud application definitions, you can choose the best cloud service provider every time you deploy your application with SixSq's cloud deployment software solution, SlipStream. To make intelligent choices, however, you need reliable and timely information about each provider.

The Service Catalog, which contains this information, is a standard feature of the SlipStream Enterprise Edition that can be activated for on-premise SlipStream installations. For the SlipStream services operated by SixSq, the Service Catalog is curently enabled on the Helix Nebula Marketplace (HNX)Nuvla, which is SixSq's online application deployment platform, will follow soon. We are currently refining and expanding the Service Catalog to provide fully automatic, policy-driven application placement. The full implementation is planned for the end of the summer, but users of HNX will see incremental improvements along the way.

To achieve this, we're changing the Service Catalog implementation through our involvement in CYCLONE, a European project funded by the H2020 program. With the proliferation of service catalogs, such as the G-Cloud Framework, GEANT, Cloud28 +, Nuvla etc, there is an opportunity to standardise the way such catalogs are presented. More information on the way we are approching this can be found on the CYCLONE website and feedback is welcome on this.


In particular, we will:

  • Create "Attribute" and "ServiceInfo" resources. The Attribute resource associates a Uniform Resource Identifier (URI) with a localized, human-readable description. The ServiceInfo resources provide values for the attributes concerning a particular cloud service provider. Together they provide a "key-value" database of facts about the cloud providers.

  • Add deployment "policies" to the application model. These policies, essentially queries over the ServiceInfo resources, select acceptable clouds and order the results from best to worst.

  • Use the policies to guide the deployment process. By applying the policies, SlipStream can then present the reduced list of acceptable clouds in the deployment dialog or select the best cloud for each component automatically.

The proposed implementation intentionally does not prescribe a schema for the Attribute and ServiceInfo resources. This allows the cloud descriptions to evolve with time and to adapt to the needs of different communities.

For HNX and Nuvla, the defined attributes will initially cover the current geographic, capacity, and pricing information. These attributes will be extended to include security information like those in the CSA Security, Trust & Assurance Registry (STAR), performance benchmarks like those in CloudHarmony, and perhaps other service information.

In the latest stable release (v2.23.2), the Attribute and ServiceInfo resources have been implemented. We are currently evaluating several backing databases to see which one provides acceptable query performance and the richest application placement policies. The best candidate currently looks to be Elasticsearch. The ability to attach deployment policies to applications will follow shortly after the database choice has been made.

If all goes as planned, you will be able to take advantage of fully automatic, policy-driven application placement by summer's end!

Addendum: The placement and ranking service is now availalble!

If you have any questions in the meantime, if you want to test out SlipStream, take a look at the Nuvla service

Go to Nuvla »

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