Hi,
The series adds a migration capability, which allows to skip shared RAM blocks
during the migration. It's useful for fast local migration. E.g. to update QEMU
for the running guests.
Usage example:
1. Start source VM:
qemu-system-x86 \
-m 4G \
-object
memory-backend-file,id=mem0,size=4G,share=on,mem-path=/dev/shm/mem0 \
-numa node,memdev=mem0 \
-qmp unix:/tmp/qemu-qmp-1.sock,server,nowait \
2. Start target VM:
qemu-system-x86 \
-m 4G \
-object
memory-backend-file,id=mem0,size=4G,share=on,mem-path=/dev/shm/mem0 \
-numa node,memdev=mem0 \
-qmp unix:/tmp/qemu-qmp-2.sock,server,nowait \
-incoming defer
3. Enable ignore-external capability on both VMs:
{ "execute": "migrate-set-capabilities" , "arguments":
{ "capabilities": [ { "capability": "x-ignore-external", "state": true } ]
} }
4. Start migration.
Another use case I keep in mind is to migrate to file. Usage is very similar.
V1 to V2:
* Keep migration stream compatibility
* Reuse the existing code to ignore unwanted RAMBlocks
* Add capability validation feature
* ignore-external -> ignore-shared
Regards,
Yury
Yury Kotov (5):
exec: Change RAMBlockIterFunc definition
migration: Move qemu_ram_foreach_migratable_block to migration code
migration: Introduce ignore-shared capability
tests/migration-test: Add a test for ignore-shared capability
migration: Add capabilities validation
exec.c | 38 ++++++-------
include/exec/cpu-common.h | 7 +--
migration/migration.c | 9 ++++
migration/migration.h | 11 +++-
migration/postcopy-ram.c | 48 +++++++++--------
migration/ram.c | 86 ++++++++++++++++++++++++++----
migration/rdma.c | 9 ++--
migration/savevm.c | 101 +++++++++++++++++++++++++++++++++++
qapi/migration.json | 5 +-
stubs/ram-block.c | 15 ++++++
tests/migration-test.c | 109 +++++++++++++++++++++++++++++++-------
util/vfio-helpers.c | 6 +--
12 files changed, 361 insertions(+), 83 deletions(-)
--
2.20.1
