Re: [Discuss-gnuradio] "Run to completion" not working with message passing blocks

[Tom Rondeau]

On Wed, Mar 25, 2015 at 3:11 AM, Piotr Krysik <address@hidden> wrote:

W dniu 16.02.2015 o 17:29, Tom Rondeau pisze:
> On Sat, Feb 14, 2015 at 3:34 PM, Piotr Krysik <address@hidden
> <mailto:address@hidden>> wrote:
>
>     W dniu 29.04.2014 o 16:20, Tom Rondeau pisze:
>     > On Tue, Apr 29, 2014 at 9:33 AM, Perper <address@hidden <mailto:address@hidden>

>     > <mailto:address@hidden <mailto:address@hidden>>> wrote:
>     >
>     >     Hi all,
>     >
>     >     I want to use message passing blocks for operations where strict
>     >     synchronization is not necessary. However in flowgraphs
>     using message
>     >     passing with "Run to completion" option turned on the
>     program doesn't
>     >     exit on last processed sample. Is this a bug?
>     >
>     >     I want to use message passing in my programs (mainly in
>     >     https://github.com/Jakotako/gr-gsm) but completion after
>     processing of
>     >     all input data is also very important for me.
>     >
>     >     --
>     >     Piotr Krysik
>     >
>     >
>     >
>     > Yes, this is a known issue and we are working on it.
>     >
>     > Tom
>     >
>     Hi Tom,
>
>     In GNU Radio 3.7.6 this is still an issue. It's quite serious because
>     whole class of applications that would use message passing and rely on
>     the processing in the flowgraph to end after processing of chunk
>     of the
>     signal (i.e. to change the flowgraph in known conditions) is not
>     possible.
>
>     I'm working on a simple gsm network monitor application based on
>     gr-gsm
>     (https://github.com/ptrkrysik/gr-gsm) and have quite hard time because
>     of this issue.
>
>     Is this some general problem where the source of it is that GNU Radio
>     was meant primarily to process stream of samples? Or is it some
>     simpler
>     matter?
>
>     I've attached vary simple flowgraph that demonstrates the problem.
>
>     Best Regards,
>     Piotr Krysik
>
>
> The fix for this was pushed a couple of weeks ago and will make it in
> the 3.7.7 release. We're looking to see any side effects and might be
> able to back-port it for the next 3.7.6 maint release. Commit here:
>
> https://github.com/gnuradio/gnuradio/commit/035b9d016dffefec890323bd0b24dbaf23aa9186
>
> Tom
>

I've tied gnuradio compiled with and without this commit. I didn't
observe difference - run to completion doesn't seem to work with message
passing. I've attached the gnuradio-companion flowgraph that I've used
for the test.

Question to the list: does "Run to completion" feature work for you in
the attached example or in any other case of a flowgraph with message
passing?

--
Piotr

Ah, well there's the problem. In GRC open up "Help"->"Types". The blocks you are using are the old Message Queue based blocks, not the new asynchronous message passing interface. The commit that I was talking about was specific to the async message passing, so yeah, it'd have no bearing on this.

This is definitely confusing since they are both "message" based even though it's a completely different system. The old style used here will likely be removed at some point, though it's use persists in a few places. For your stuff, I'd avoid using this (anything with that dark grey port) and use the new async messages (the light grey ports).

Tom