[systemd-devel] [RFC 4/8] HACK0: allow meta information customizable

[Daniel Mack]

On 06/27/2014 11:06 AM, AKASHI Takahiro wrote:
> On 06/27/2014 01:32 AM, Daniel Mack wrote:
>> On 06/26/2014 12:33 PM, AKASHI Takahiro wrote:

>>> Assuming that attaching meta is necessary but its also expensive, it might be a good idea
>>> to have and check meta info not per message, but per connection. (In this case, we may have to
>>> invent higher-level protocol/concept).
>>
>> That's impossible because the information can change during a
>> connection's lifetime, and we make the promise of sending accurate,
>> up-to-date information along with each message, if the user requested it.
> 
> Caching meta info might be a help, I have no specific idea though.

No, that's what I'm saying. We cannot cache anything as any information
may change at any time. The rule here is simple: if you want metadata,
you have to be aware that they come at a price. If you don't need them,
don't request them :)


Thanks,
Daniel