From: "Michael R. Hines" <mrhi...@us.ibm.com> Changes since v4:
- Added new QEMUFileOps function: qemu_get_max_size() - Renamed capability to x-pin-all, disabled by default - Added numbers for x-pin-all to performance section in docs/rdma.txt - Included performance numbers in this cover letter - Converted throughput patch to a MigrationStats statistic in QMP - Better QMP error message delivery - Updated documentation - Moved docs/rdma.txt up to top of patch series - Fixed all v4 changes requested - Finished additional cleanup requests - Updated copyright for migration-rdma.c Wiki: http://wiki.qemu.org/Features/RDMALiveMigration Github: g...@github.com:hinesmr/qemu.git Here is a brief summary of total migration time and downtime using RDMA: Using a 40gbps infiniband link performing a worst-case stress test, using an 8GB RAM virtual machine: Using the following command: $ apt-get install stress $ stress --vm-bytes 7500M --vm 1 --vm-keep RESULTS: 1. Migration throughput: 26 gigabits/second. 2. Downtime (stop time) varies between 15 and 100 milliseconds. EFFECTS of memory registration on bulk phase round: For example, in the same 8GB RAM example with all 8GB of memory in active use and the VM itself is completely idle using the same 40 gbps infiniband link: 1. x-pin-all disabled total time: approximately 7.5 seconds @ 9.5 Gbps 2. x-pin-all enabled total time: approximately 4 seconds @ 26 Gbps These numbers would of course scale up to whatever size virtual machine you have to migrate using RDMA. Enabling this feature does *not* have any measurable affect on migration *downtime*. This is because, without this feature, all of the memory will have already been registered already in advance during the bulk round and does not need to be re-registered during the successive iteration rounds. Michael R. Hines (12): rdma: add documentation rdma: export yield_until_fd_readable() rdma: export throughput w/ MigrationStats QMP rdma: introduce qemu_get_max_size() rdma: introduce qemu_file_mode_is_not_valid() rdma: export qemu_fflush() rdma: introduce ram_handle_compressed() rdma: introduce qemu_ram_foreach_block() rdma: new QEMUFileOps hooks rdma: introduce capability x-rdma-pin-all rdma: core logic rdma: send pc.ram Makefile.objs | 1 + arch_init.c | 59 +- configure | 29 + docs/rdma.txt | 404 ++++++ exec.c | 9 + hmp.c | 2 + include/block/coroutine.h | 6 + include/exec/cpu-common.h | 5 + include/migration/migration.h | 24 + include/migration/qemu-file.h | 44 + migration-rdma.c | 2727 +++++++++++++++++++++++++++++++++++++++++ migration.c | 22 +- qapi-schema.json | 12 +- qemu-coroutine-io.c | 23 + savevm.c | 133 +- 15 files changed, 3451 insertions(+), 49 deletions(-) create mode 100644 docs/rdma.txt create mode 100644 migration-rdma.c -- 1.7.10.4
