Postcopy Preemption - Peter Xu, Red Hat
Channel: The Linux Foundation
Date: 2022-10-08

Postcopy Preemption - Peter Xu, Red Hat

In this session, Peter Xu will introduce a new postcopy feature called QEMU postcopy preemption. Postcopy preemption a performance feature to speed up page request handling during postcopy phase. It majorly solves two issues regarding postcopy: (1) providing postcopy with its own migration channel for urgent pages, and (2) allowing interruptions to the migration stream during sending a huge page. Some background information regarding postcopy will be covered, on how it's generally working, how it compares with precopy solutions, and how postcopy preemption helps postcopy to achieve a lower page fault latencies. There will also be discussions about follow up possible enhancements to postcopy especially regarding to hugetlbfs pages, for example, with the kernel capability to map the huge pages with different granularities.