Re: [Qemu-devel] [PATCH 2/3] migration: Remove use of old MigrationParams

[Juan Quintela <quintela@redhat.com>]

Hailiang Zhang <zhang.zhanghailiang@huawei.com> wrote:
> Hi,
>
>>> Hmm you don't seem to have replaced this with anything.
>>> I think that's a behavioural change; the trick COLO did (I'm not sure if this
>>> is still the way it works) is that they initiate the first migration
>>> with block migration enabled so that the two hosts (with non-shared storage)
>>> get sync'd storage, and then at the completion of that first migration
>>> they then switch into the checkpointing mode where they're only
>>> doing updates - that's why it gets switched off at this point
>>> prior to the 1st checkpoint.
>>
>> Weird, really.
>>
>> I did't catch that.
>>
>> Will investigate.
>
> Yes, Dave is right, for non-shared disk, we need to enable block
> migration for first cycle,
> to sync the disks of two sides. After that, qemu will go into COLO
> state which we need to
> disable block migration.

v2 posted.

My understanding is that it maintains the sematic, please test/comment.

Thanks, Juan.