[libvirt] [PATCH 5/8] latency: Update monitor functions for new latency fields

[Osier Yang]

于 2011年09月02日 18:17, Daniel Veillard 写道:
> On Wed, Aug 31, 2011 at 04:26:10PM +0800, Osier Yang wrote:
>> The mainly changes are:
>>
>> 1) Update qemuMonitorGetBlockStatsInfo and it's children (Text/JSON)
>>     functions to return the value of new latency fields.
>> 2) Add new function qemuMonitorGetBlockStatsParamsNumber, which is
>>     to count how many parameters the underlying QEMU supports.
>> 3) Update virDomainBlockStats in src/qemu/qemu_driver.c to be
>>     compatible with the changes by 1).
>    I'm not sure we should extend the existing set of function
> used by GetBlockStats instead of creating new functions asking/looking
> for the full set of values. On one hand it's good to share the code,
> but on the other hand if this leads to more round-trip between
> libvirtd and qemu I would rather keep them separate. I.e. we should
> pay the extra cost only when asking for the extra data.
>
> Daniel

I considered to extend the existing functions to get the params
number, such as add a new flag argument to the function. But
after thinking a while, I think it's more clear to keep them as
seperate functions.

And on the other hand, yes, it costs much on the wire between
qemu and libvirtd, we only want the extra info when needs.

So personally I'd perfer to keep them seperate.

Thanks,
Osier