[systemd-devel] KDBus Signals and Timeouts

[Justin Brown]

On Mon, Feb 24, 2014 at 11:59 PM, Kay Sievers <kay at vrfy.org> wrote:
> On Tue, Feb 25, 2014 at 4:26 AM, Justin Brown <justin.brown at fandingo.org> wrote:
>> I've been reading over some of the articles about KDBus and have a
>> question about reclaiming memfds. Let's say that I have a process
>> which is sending out a large amount of data over lots of signals, and
>> there are more than one potential subscriber. Is there (or will there
>> be) any mechanism that these signals can "expire" after some
>> conditions are met, or will the data just continue to build-up in each
>> subscriber until it frees the memfds? Additionally, would there be a
>> way to automatically expire these signals after a period of time,
>> once a certain number of signals are received, or preferably once a
>> certain amount of data are received? If that is (or will be) possible,
>> any idea how the subscriber would be handle signals expiring.
>
> Memfds or other fds cannot be broadcasted, only attached to directed messages.
>
> Kay

Thanks for the response. In that case, how efficient are signals in
comparison to methods with kdbus? I was under the impression that
memfds are one of the fundamental reason that kdbus will be suitable
for sending large data payloads.

Thanks,
Justin