Re: [Qemu-devel] [PATCH 5/6] Purge migration of (almost) everything to do with monitors

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2012-02-15 13:53, Luiz Capitulino wrote:
> On Wed, 15 Feb 2012 10:02:54 +0100
> Jan Kiszka <jan.kiszka@siemens.com> wrote:
> 
>> On 2012-02-10 20:31, Luiz Capitulino wrote:
>>> The Monitor object is passed back and forth within the migration/savevm
>>> code so that it can print errors and progress to the user.
>>>
>>> However, that approach assumes a HMP monitor, being completely invalid
>>> in QMP.
>>>
>>> This commit drops almost every single usage of the Monitor object, all
>>> monitor_printf() calls have been converted into DPRINTF() ones.
>>
>> Particularly NACK on this. Either the information is useless anyway,
>> then remove it. Otherwise, keep it for channels that can properly
>> display it (AKA HMP). I bet the latter can easily be achieved by
>> providing non-printing Monitor objects over QMP instances.
> 
> I will consider dropping it :)
> 
> I can think of two ways of displaying status in HMP (considering the new
> HMP/QMP split design):
> 
>  1. We add all progress status information to a query command, and let HMP
>     poll it (manually by the user or automatically from a timer)

As migration can also be synchronous, polling has to be time-driven.

> 
>  2. We emit an event whenever the progress status changes (seems a bit overkill)

If there is a use in QMP as well... dunno.

Jan

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