This is the 13th version of COLO (Still only support periodic checkpoint).
Here is only COLO frame part, you can get the whole codes from github:
https://github.com/coloft/qemu/commits/colo-v2.4-periodic-mode
Please ignore patch 4 ~ 5 which have been picked by Dave into another series.
Test procedure:
1. Startup qemu
Primary side:
#x86_64-softmmu/qemu-system-x86_64 -enable-kvm -boot c -m 2048 -smp 2 -qmp
stdio -vnc :7 -name primary -cpu qemu64,+kvmclock -device piix3-usb-uhci
-device usb-tablet -netdev tap,id=hn0,vhost=off -device
virtio-net-pci,id=net-pci0,netdev=hn0 -drive
if=virtio,id=colo-disk0,driver=quorum,read-pattern=fifo,vote-threshold=1,children.0.file.filename=/mnt/sdd/pure_IMG/linux/redhat/rhel_6.5_64_2U_ide,children.0.driver=raw
Secondary side:
#x86_64-softmmu/qemu-system-x86_64 -boot c -m 2048 -smp 2 -qmp stdio -vnc :7
-name secondary -enable-kvm -cpu qemu64,+kvmclock -device piix3-usb-uhci
-device usb-tablet -netdev tap,id=hn0,vhost=off -device
virtio-net-pci,id=net-pci0,netdev=hn0 -drive
if=none,id=colo-disk0,file.filename=/mnt/sdd/pure_IMG/linux/redhat/rhel_6.5_64_2U_ide,driver=raw,node-name=node0
-drive
if=virtio,id=active-disk0,throttling.bps-total=70000000,driver=replication,mode=secondary,file.driver=qcow2,file.file.filename=/mnt/ramfs/active_disk.img,file.backing.driver=qcow2,file.backing.file.filename=/mnt/ramfs/hidden_disk.img,file.backing.backing=colo-disk0
-incoming tcp:0:8888
2. On Secondary VM's QEMU monitor, issue command
{'execute':'qmp_capabilities'}
{'execute': 'nbd-server-start', 'arguments': {'addr': {'type': 'inet', 'data':
{'host': '192.168.2.88', 'port': '8889'} } } }
{'execute': 'nbd-server-add', 'arguments': {'device': 'colo-disk0', 'writable':
true } }
{'execute': 'trace-event-set-state', 'arguments': {'name': 'colo*', 'enable':
true} }
3. On Primary VM's QEMU monitor, issue command:
{'execute':'qmp_capabilities'}
{'execute': 'human-monitor-command', 'arguments': {'command-line': 'drive_add
buddy
driver=replication,mode=primary,file.driver=nbd,file.host=9.61.1.7,file.port=8889,file.export=colo-disk0,node-name=node0,if=none'}}
{'execute':'x-blockdev-change', 'arguments':{'parent': 'colo-disk0', 'node':
'node0' } }
{'execute': 'migrate-set-capabilities', 'arguments': {'capabilities': [
{'capability': 'x-colo', 'state': true } ] } }
{'execute': 'migrate', 'arguments': {'uri': 'tcp:192.168.2.88:8888' } }
4. After the above steps, you will see, whenever you make changes to PVM, SVM
will be synced.
You can by issue command '{ "execute": "migrate-set-parameters" , "arguments":{
"x-checkpoint-delay": 2000 } }'
to change the checkpoint period time.
5. Failover test
You can kill Primary VM and run 'x_colo_lost_heartbeat' in Secondary VM's
monitor at the same time, then SVM will failover and client will not feel this
change.
Before issuing '{ "execute": "x-colo-lost-heartbeat" }' command, we have to
issue block related command to stop block replication.
Primary:
Remove the nbd child from the quorum:
{ 'execute': 'x-blockdev-change', 'arguments': {'parent': 'colo-disk0',
'child': 'children.1'}}
Note: there is no qmp command to remove the blockdev now
Secondary:
The primary host is down, so we should do the following thing:
{ 'execute': 'nbd-server-stop' }
Please review, thanks.
TODO:
1. Checkpoint based on proxy in qemu
2. The capability of continuous FT
3. Optimize the VM's downtime during checkpoint
v13:
- Refactor colo_*_cmd helper functions to use 'Error **errp' parameter
instead of return value to indicate success or failure. (patch 10)
- Remove the optional error message for COLO_EXIT event. (patch 25)
- Use semaphore to notify colo/colo incoming loop that failover work is
finished. (patch 26)
- Move COLO shutdown related codes to colo.c file. (patch 28)
- Fix memory leak bug for colo incoming loop. (new patch 31)
- Re-use some existed helper functions to realize the process of
saving/loading ram and device. (patch 32)
- Fix some other comments from Dave and Markus.
v12:
- Fix the bug that default buffer filter broken vhost-net.
- Add an flag in struct NetFilterState to help skipping default
filter for packets travelling through filter layer.
- Remove the default failover treatment which may cause split-brain.
- Rename checkpoint-delay to x-checkpoint-delay.
- Check if all netdev supports default filter before going into COLO.
- Reconstruct send/receive helper functions in patch 10.
- Address serveral other comments from Dave
v11:
- Re-implement buffer/release packets based on filter-buffer according
to Jason Wang's suggestion. (patch 34, patch 36 ~ patch 38)
- Rebase master to re-use some stuff introduced by post-copy.
- Address several comments from Eric and Dave, the fixing record can
be found in each patch.
v10:
- Rename 'colo_lost_heartbeat' command to experimental 'x_colo_lost_heartbeat'
- Rename migration capability 'colo' to 'x-colo' (Eric's suggestion)
- Simplify the process of primary side by dropping colo thread and reusing
migration thread. (Dave's suggestion)
- Add several netfilter related APIs to support buffer/release packets
for COLO (patch 32 ~ patch 36)
zhanghailiang (39):
configure: Add parameter for configure to enable/disable COLO support
migration: Introduce capability 'x-colo' to migration
COLO: migrate colo related info to secondary node
migration: Export migrate_set_state()
migration: Add state records for migration incoming
migration: Integrate COLO checkpoint process into migration
migration: Integrate COLO checkpoint process into loadvm
migration: Rename the'file' member of MigrationState
COLO/migration: Create a new communication path from destination to
source
COLO: Implement colo checkpoint protocol
COLO: Add a new RunState RUN_STATE_COLO
QEMUSizedBuffer: Introduce two help functions for qsb
COLO: Save PVM state to secondary side when do checkpoint
ram: Split host_from_stream_offset() into two helper functions
COLO: Load PVM's dirty pages into SVM's RAM cache temporarily
ram/COLO: Record the dirty pages that SVM received
COLO: Load VMState into qsb before restore it
COLO: Flush PVM's cached RAM into SVM's memory
COLO: Add checkpoint-delay parameter for migrate-set-parameters
COLO: synchronize PVM's state to SVM periodically
COLO failover: Introduce a new command to trigger a failover
COLO failover: Introduce state to record failover process
COLO: Implement failover work for Primary VM
COLO: Implement failover work for Secondary VM
qmp event: Add COLO_EXIT event to notify users while exited from COLO
COLO failover: Shutdown related socket fd when do failover
COLO failover: Don't do failover during loading VM's state
COLO: Process shutdown command for VM in COLO state
COLO: Update the global runstate after going into colo state
savevm: Split load vm state function qemu_loadvm_state
savevm: Introduce two helper functions for save/find loadvm_handlers
entry
COLO: Separate the process of saving/loading ram and device state
COLO: Split qemu_savevm_state_begin out of checkpoint process
net/filter-buffer: Add default filter-buffer for each netdev
filter-buffer: Accept zero interval
filter-buffer: Introduce a helper function to enable/disable default
filter
filter-buffer: Introduce a helper function to release packets
colo: Use default buffer-filter to buffer and release packets
COLO: Add block replication into colo process
configure | 11 +
docs/qmp-events.txt | 16 +
hmp-commands.hx | 15 +
hmp.c | 15 +
hmp.h | 1 +
include/exec/ram_addr.h | 9 +-
include/migration/colo.h | 40 +++
include/migration/failover.h | 33 ++
include/migration/migration.h | 21 +-
include/migration/qemu-file.h | 3 +-
include/net/filter.h | 12 +
include/net/net.h | 5 +
include/sysemu/sysemu.h | 9 +
migration/Makefile.objs | 2 +
migration/colo-comm.c | 71 ++++
migration/colo-failover.c | 83 +++++
migration/colo.c | 804 ++++++++++++++++++++++++++++++++++++++++++
migration/exec.c | 4 +-
migration/fd.c | 4 +-
migration/migration.c | 216 ++++++++----
migration/postcopy-ram.c | 6 +-
migration/qemu-file-buf.c | 61 ++++
migration/ram.c | 213 +++++++++--
migration/rdma.c | 2 +-
migration/savevm.c | 248 +++++++++----
migration/tcp.c | 4 +-
migration/unix.c | 4 +-
net/filter-buffer.c | 127 ++++++-
net/filter.c | 6 +-
net/net.c | 58 +++
qapi-schema.json | 104 +++++-
qapi/event.json | 15 +
qmp-commands.hx | 24 +-
stubs/Makefile.objs | 1 +
stubs/migration-colo.c | 45 +++
trace-events | 10 +
vl.c | 30 +-
37 files changed, 2135 insertions(+), 197 deletions(-)
create mode 100644 include/migration/colo.h
create mode 100644 include/migration/failover.h
create mode 100644 migration/colo-comm.c
create mode 100644 migration/colo-failover.c
create mode 100644 migration/colo.c
create mode 100644 stubs/migration-colo.c