Fast restore of checkpointed memory using working set estimation
Irene Y. Zhang, Alex Garthwaite, Yury Baskakov, Kenneth C. Barr · 2011
In order to make save and restore features practical, saved virtual machines (VMs) must be able to quickly restore to normal operation. Unfortunately, fetching a saved memory image from persistent storage can be slow, especially as VMs grow in memory size. One possible solution for reducing this time is to lazily restore memory after the VM starts. However, accesses to unrestored memory after the VM starts can degrade performance, sometimes rendering the VM unusable for even longer. Existing performance metrics do not account for performance degradation after the VM starts, making it difficult to compare lazily restoring memory against other approaches. In this paper, we propose both a better metric for evaluating the performance of different restore techniques and a better scheme for restoring saved VMs.