Recommendations: Virtualization (FAST Search Server 2010 for SharePoint)

FAST Search Server 2010

Applies to: FAST Search Server 2010

Topic Last Modified: 2011-03-15

This article describes virtualization recommendations for Microsoft FAST Search Server 2010 for SharePoint. For a complete recommendations overview, refer to Performance and capacity recommendations (FAST Search Server 2010 for SharePoint).

FAST Search Server 2010 for SharePoint supports virtualization, but for larger deployments, we recommend that you only use virtualization for your test and development environments- not the production environment. Our rationale is as follows:

  • FAST Search Server 2010 for SharePoint is a heavy user of CPU and IO

  • Virtual machines only have access to a limited number of CPU cores (Hyper-V = 4, VM ware = 8)

  • Virtual machines will give 30-40% decrease in overall performance

For smaller deployments, virtualization might be a good alternative for production environments even though the performance decreases. We tested virtualization within the extra-small test scenario (with up to 8 million items) and got the following results:

Overall, the virtual deployments showed 35-70% decrease in crawling and indexing performance compared to the deployments running on physical hardware. Even when crawls were not running, the virtualized deployments had a significantly lower query performance with more variation than the non-virtualized options. During a full crawl, the virtualized deployments had over 10 QPS. The non-virtualized deployments had more than five times the throughput. The performance reduction was related to the storage performance in addition to the search components having a limited number of CPU cores at disposal.

For more information of the test environment, refer to Test results: Extra-small scenario (FAST Search Server 2010 for SharePoint).

FAST Search Server 2010 for SharePoint can be installed on virtual environments that use task offloading. Task offloading reduce load on the CPU caused by the construction, framing and validating of network packets and maintaining network sessions (TCP), but we recommend that you disable this feature because it causes decreased crawl performance.