vMotion Architecture, Performance, and Best Practices in VMware vSphere 5

VMware’s Sreekanth Setty who works as a staff member at the Performance Engineering team has published  a great technical white-paper regarding vMotion Architecture, Performance, and Best Practices in VMware vSphere 5.

VMware vSphere vMotion is one of the most popular features of VMware vSphere. vMotion provides invaluable benefits to administrators of virtualized datacenters. It enables load balancing, helps prevent server downtime, enables troubleshooting and provides flexibility—with no perceivable impact on application availability and responsiveness.

vSphere 5 includes a number of performance enhancements and new features that have been introduced in vMotion. Among these improvements are a multiple–network adaptor capability for vMotion, better utilization of 10GbE bandwidth, Metro vMotion, and optimizations to further reduce impact on application performance.

A series of tests were conducted to quantify the performance gains of vMotion in vSphere 5 over vSphere 4.1 in a number of scenarios including Web servers, messaging servers and database servers. An evacuation scenario was also performed in which a large number of virtual machines were migrated.

Test results show the following:

• Improvements in vSphere 5 over vSphere 4.1 are twofold: the duration of vMotion and the impact on application performance during vMotion.
• There are consistent performance gains in the range of 30% in vMotion duration on vSphere 5, due to the optimizations introduced in vMotion in vSphere 5.
• The newly added multi–network adaptor feature in vSphere 5 results in dramatic improvements in performance (for example, duration time is reduced by more than a 3x factor) in vSphere 5 over vSphere 4.1.