Re: [Qemu-devel] [RFC PATCH v4 00/28] COarse-grain LOck-stepping(COLO) Virtual Machines for Non-stop Service

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* zhanghailiang (zhang.zhanghailiang@huawei.com) wrote:
> On 2015/5/14 20:14, Dr. David Alan Gilbert wrote:
> >* zhanghailiang (zhang.zhanghailiang@huawei.com) wrote:
> >>This is the 4th version of COLO, here is only COLO frame part, include: VM checkpoint,
> >>failover, proxy API, block replication API, not include block replication.
> >>The block part has been sent by wencongyang:
> >>[RFC PATCH COLO v2 00/13] Block replication for continuous checkpoints
> >>
> >>Compared with last version, there aren't too much optimize and new functions.
> >>The main reason is that there is an known issue that still unsolved, we found
> >>some dirty pages which have been missed setting bit in corresponding bitmap.
> >>And it will trigger strange problem in VM.
> >>We hope to resolve it before add more codes.
> >>
> >>You can get the newest integrated qemu colo patches from github:
> >>https://github.com/coloft/qemu/commits/colo-v1.1
> >
> >I thought I'd just say I've got the remotes/origin/colo_huawei_v4.7 off Wen's
> >git running here on one of my pair of machines.
> >
> >This set of hosts is mostly OK running colo; the proxy module still gets
> >upset sometimes; but mostly on errors;  if the colo-proxy-script fails
> >during startup, I get RCU stalls; but if the script works, colo normally
> >works on this setup.
> 
> Hi Dave,
> 
> I'm trying to optimize the proxy module codes, and yes, the 'lock' we used in proxy module
> was a little messy before, and i have finished rewriting the part of communication between qemu
> and proxy, also removing the parameter of xt_PMYCOLO module ...

Good; that should be a lot better.

> There are still some further tests need to be done, i will finish it as soon as possible.
> I hope to send the next version in next week. And you can test the branch of Wen's temporarily,
> Except block part, there is no difference in COLO framework between his branch and mine. ;)

I'll be happy to try that.

Dave

> 
> Thanks,
> zhanghailiang
> 
> 
> >
> >>About how to test COLO, Please reference to the follow link.
> >>http://wiki.qemu.org/Features/COLO.
> >>
> >>Please review and test.
> >>
> >>Known issue still unsolved:
> >>(1) Some pages dirtied without setting its corresponding dirty-bitmap.
> >>
> >>Previous posted RFC patch series:
> >>http://lists.nongnu.org/archive/html/qemu-devel/2014-06/msg05567.html
> >>http://lists.nongnu.org/archive/html/qemu-devel/2014-09/msg04459.html
> >>https://lists.gnu.org/archive/html/qemu-devel/2015-02/msg04771.html
> >>
> >>TODO list:
> >>1 Optimize the process of checkpoint, shorten the time-consuming:
> >>   (Partly done, patch is not include into this series)
> >>    1) separate ram and device save/load process to reduce size of extra memory
> >>       used during checkpoint
> >>    2) live migrate part of dirty pages to slave during sleep time.
> >>2 Add more debug/stat info
> >>   (Partly done, patch is not include into this series)
> >>   include checkpoint count, proxy discompare count, downtime,
> >>    number of live migrated pages, total sent pages, etc.
> >>3 Strengthen failover
> >>4 optimize proxy part, include proxy script.
> >>5 The capability of continuous FT
> >>
> >>v4:
> >>- New block replication scheme (use image-fleecing for sencondary side)
> >>- Adress some comments from Eric Blake and Dave
> >>- Add commmand colo-set-checkpoint-period to set the time of periodic checkpoint
> >>- Add a delay (100ms) between continuous checkpoint requests to ensure VM
> >>   run 100ms at least since last pause.
> >>
> >>v3:
> >>- use proxy instead of colo agent to compare network packets
> >>- add block replication
> >>- Optimize failover disposal
> >>- handle shutdown
> >>
> >>v2:
> >>- use QEMUSizedBuffer/QEMUFile as COLO buffer
> >>- colo support is enabled by default
> >>- add nic replication support
> >>- addressed comments from Eric Blake and Dr. David Alan Gilbert
> >>
> >>v1:
> >>- implement the frame of colo
> >>
> >>Wen Congyang (1):
> >>   COLO: Add block replication into colo process
> >>
> >>zhanghailiang (27):
> >>   configure: Add parameter for configure to enable/disable COLO support
> >>   migration: Introduce capability 'colo' to migration
> >>   COLO: migrate colo related info to slave
> >>   migration: Integrate COLO checkpoint process into migration
> >>   migration: Integrate COLO checkpoint process into loadvm
> >>   COLO: Implement colo checkpoint protocol
> >>   COLO: Add a new RunState RUN_STATE_COLO
> >>   QEMUSizedBuffer: Introduce two help functions for qsb
> >>   COLO: Save VM state to slave when do checkpoint
> >>   COLO RAM: Load PVM's dirty page into SVM's RAM cache temporarily
> >>   COLO VMstate: Load VM state into qsb before restore it
> >>   arch_init: Start to trace dirty pages of SVM
> >>   COLO RAM: Flush cached RAM into SVM's memory
> >>   COLO failover: Introduce a new command to trigger a failover
> >>   COLO failover: Implement COLO master/slave failover work
> >>   COLO failover: Don't do failover during loading VM's state
> >>   COLO: Add new command parameter 'colo_nicname' 'colo_script' for net
> >>   COLO NIC: Init/remove colo nic devices when add/cleanup tap devices
> >>   COLO NIC: Implement colo nic device interface configure()
> >>   COLO NIC : Implement colo nic init/destroy function
> >>   COLO NIC: Some init work related with proxy module
> >>   COLO: Do checkpoint according to the result of net packets comparing
> >>   COLO: Improve checkpoint efficiency by do additional periodic
> >>     checkpoint
> >>   COLO: Add colo-set-checkpoint-period command
> >>   COLO NIC: Implement NIC checkpoint and failover
> >>   COLO: Disable qdev hotplug when VM is in COLO mode
> >>   COLO: Implement shutdown checkpoint
> >>
> >>  arch_init.c                            | 199 +++++++-
> >>  configure                              |  14 +
> >>  hmp-commands.hx                        |  30 ++
> >>  hmp.c                                  |  14 +
> >>  hmp.h                                  |   2 +
> >>  include/exec/cpu-all.h                 |   1 +
> >>  include/migration/migration-colo.h     |  58 +++
> >>  include/migration/migration-failover.h |  22 +
> >>  include/migration/migration.h          |   3 +
> >>  include/migration/qemu-file.h          |   3 +-
> >>  include/net/colo-nic.h                 |  25 +
> >>  include/net/net.h                      |   4 +
> >>  include/sysemu/sysemu.h                |   3 +
> >>  migration/Makefile.objs                |   2 +
> >>  migration/colo-comm.c                  |  80 ++++
> >>  migration/colo-failover.c              |  48 ++
> >>  migration/colo.c                       | 809 +++++++++++++++++++++++++++++++++
> >>  migration/migration.c                  |  60 ++-
> >>  migration/qemu-file-buf.c              |  58 +++
> >>  net/Makefile.objs                      |   1 +
> >>  net/colo-nic.c                         | 438 ++++++++++++++++++
> >>  net/tap.c                              |  45 +-
> >>  qapi-schema.json                       |  42 +-
> >>  qemu-options.hx                        |  10 +-
> >>  qmp-commands.hx                        |  41 ++
> >>  savevm.c                               |   2 +-
> >>  scripts/colo-proxy-script.sh           |  97 ++++
> >>  stubs/Makefile.objs                    |   1 +
> >>  stubs/migration-colo.c                 |  58 +++
> >>  vl.c                                   |  36 +-
> >>  30 files changed, 2178 insertions(+), 28 deletions(-)
> >>  create mode 100644 include/migration/migration-colo.h
> >>  create mode 100644 include/migration/migration-failover.h
> >>  create mode 100644 include/net/colo-nic.h
> >>  create mode 100644 migration/colo-comm.c
> >>  create mode 100644 migration/colo-failover.c
> >>  create mode 100644 migration/colo.c
> >>  create mode 100644 migration/colo.c.
> >>  create mode 100644 net/colo-nic.c
> >>  create mode 100755 scripts/colo-proxy-script.sh
> >>  create mode 100644 stubs/migration-colo.c
> >>
> >>--
> >>1.7.12.4
> >>
> >>
> >--
> >Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
> >
> >.
> >
> 
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK