* Yury Kotov (yury-ko...@yandex-team.ru) wrote:
> 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.
Hi,
I've cc'd in Eric, Lai and Peter, all who were asking for something
similar last year; can you all confirm this patch does what you need or
can work with what you needed to do?
Dave
> 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
>
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
