[zeromq-dev] What's a tickless timer?

Apostolis Xekoukoulotakis xekoukou at gmail.com
Tue Feb 5 20:37:59 CET 2013


Let me say one of my use cases that, i think cant be handled by timers.
This is WIP.

I have in each thread multiple actors. Each such actor might want to ask
for a service (like a database).
It sends a message and then work passes to other actors. Since there is a
chance that the response from the service is lost,
I want to use the lazy pirate pattern per actor. So what I did was add a
tickless service with poll
 that sends msgs to a socket (or directly to the same thread that has the
poll ) after a specific delay.

I think that having payloads on timers is a useful pattern in general.

2013/2/5 Pieter Hintjens <ph at imatix.com>

> On Tue, Feb 5, 2013 at 5:35 PM, Apostolis Xekoukoulotakis
> <xekoukou at gmail.com> wrote:
>
> > If you have a timer to expire after 1m , you dont check every 20 ms if it
> > expired, you use poll() that wakes after 1m if no other event happens.
>
> Right. The original goal is to reduce CPU wakeups, so tickless code
> will work nicely on low power devices. The concept comes from the
> Linux kernel: https://lesswatts.org/projects/tickless/
>
> As well as reducing CPU wakeups it makes it easier to schedule precise
> events, e.g. send PING once per second, even if there was some other
> activity in the meantime. You need this when you are doing anything
> complex.
>
> zmq_poll should IMO have tickless timers built in, and it's something
> I'd like to add to CZMQ (poll class with tickless timers).
>
> -Pieter
> _______________________________________________
> zeromq-dev mailing list
> zeromq-dev at lists.zeromq.org
> http://lists.zeromq.org/mailman/listinfo/zeromq-dev
>



-- 


Sincerely yours,

     Apostolis Xekoukoulotakis
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.zeromq.org/pipermail/zeromq-dev/attachments/20130205/412efbd1/attachment.html>


More information about the zeromq-dev mailing list