On Tue, Feb 20, 2024 at 07:41:04PM -0300, Fabiano Rosas wrote: > Latest numbers > ============== > > => guest: 128 GB RAM - 120 GB dirty - 1 vcpu in tight loop dirtying memory > => host: 128 CPU AMD EPYC 7543 - 2 NVMe disks in RAID0 (8586 MiB/s) - xfs > => pinned vcpus w/ NUMA shortest distances - average of 3 runs - results > from query-migrate > > non-live | time (ms) pages/s mb/s MB/s > -------------------+----------------------------------- > file | 110512 256258 9549 1193 > + bg-snapshot | 245660 119581 4303 537
Is this the one using userfault? I'm surprised it's much slower when enabled; logically for a non-live snapshot it should take similar loops like a normal migration as it should have zero faults, then it should be similar performance. > -------------------+----------------------------------- > fixed-ram | 157975 216877 6672 834 > + multifd 8 ch. | 95922 292178 10982 1372 > + direct-io | 23268 1936897 45330 5666 > ------------------------------------------------------- > > live | time (ms) pages/s mb/s MB/s > -------------------+----------------------------------- > file | - - - - (file grew 4x the VM > size) > + bg-snapshot | 357635 141747 2974 371 > -------------------+----------------------------------- > fixed-ram | - - - - (no convergence in 5 > min) > + multifd 8 ch. | 230812 497551 14900 1862 > + direct-io | 27475 1788025 46736 5842 > ------------------------------------------------------- Also surprised on direct-io too.. that is definitely something tremendous. -- Peter Xu
