April 15, 2012
Live migration is a key technology in today’s shared-pool datacenters. However, with the number of resources managed by a VM increases, migrating a VM among machine nodes tends to be more and more time-consuming and intrusive, and thus likely hurts application performance and even disrupts running services. Even worse, recent practices of including a local storage cache such as flash memory between a VM and its networked storage creates more challenges to live VM migration, as it is usually necessary to migrate the storage cache (which is usually in the scale of 10s to 100s GB) along with the VM itself, to avoid spending hours or even days for a VM to achieve its optimal performance.In this project, we aim at reducing both the migration time and downtime in migrating a VM in shared-pool datacenter with local storage cache. Being aware of the existence of multiple NICs and multiple cores in typical off-the-shelf servers, we propose to parallelize the tracking of dirty pages and disk blocks in local cache as well as the transmitting of memory pages and disk blocks using multiple NICs and CPU cores. Our investigation would gain a more comprehensive understanding of live VM migration with local storage caches. The proposed approach could also significantly reduce the migration time as well as the downtime.