[PD-dev] plans for next Pd release

[Edwin van der Heide]

Dear Christof,

Your distinction of the three categories makes a lot of sense.

Very nice to see the PR for the ‘asynchronous tasks API’ that provides a general infrastructure.

Best! Edwin

On 17 Jul 2021, at 15:49, Christof Ressi <info at christofressi.com> wrote:


> 
> Am I right to assume that this would include writing arrays to disk without interfering with the audio thread?
I don't think so, but there's already a separate PR for that: https://github.com/pure-data/pure-data/pull/1357

Actually, I am not sure what Giulio meant with "disk I/O". Maybe that the I/O thread could also be used to stream audio to/from disk? Personally, I would keep networking and audio streaming on different threads as they don't necessarily have the same priority.

---

Generally, I see three categories of worker threads:

1) the task has to meet a certain deadline. One example is streaming audio to/from disk: it eventually has to happen within a certain time frame, but the time frame can be made larger with additional buffering.

2) the task has no deadline but should be completed as fast as possible. One example is network I/O.

3) the task has no time constraints at all. One example is loading soundfiles from disk: you don't really care how much time it takes, the only important thing is that it doesn't block other threads.

Supercollider's original "scsynth" Server has a thread for disk streaming (1) plus a thread for asynchronous tasks which includes outgoing network packets (2 + 3). The latter is not ideal, because it means that networking can be temporarily blocked by time consuming tasks. For this reason, the more recent "supernova" Server has a dedicated thread for outgoing network packets.

Christof

On 17.07.2021 14:45, Edwin van der Heide wrote:
> Dear Giulio,
> 
> Am I right to assume that this would include writing arrays to disk without interfering with the audio thread?
> 
> Best! Edwin
> 
>> On 16 Jul 2021, at 00:18, Giulio Moro via Pd-dev <pd-dev at lists.iem.at> wrote:
>> 
>> I have had this PR open for a while: https://github.com/pure-data/pure-data/pull/1261 . It adds threaded behaviour for disk and network I/O, making the Pd audio thread "real-time safer". I went through quite a few revisions courtesy of umlaeute and Spacechild1, but haven't heard from you directly. I am happy to do some more work if there is interest in merging. CI build currently fails because of weird "support" of ssize_t on VS (happy to hear about workarounds).
>> Best,
>> Giulio
>> 
>> 
>> Miller Puckette via Pd-dev wrote on 13/07/2021 19:22:
>>> (re-send - I had sent to pd-dev at iem.at but that now seems to be defunct...)
>>> To Pd dev -
>>> I'm going to try to get the next Pd release (0.52) out over the next month
>>> or two.  My personal priorities for this release would be putting in a message
>>> backtrace mechanism (by overriding canvas_connect and pd_bind to go through
>>> small proxy objects; this will have to be done at load time I think) and
>>> to go back and try to figure out how to do tooltips without adding cruft to
>>> the inlet structure.  (There's an ancient source-patch to provide tooltips
>>> by Chris McCormichadn Guenter Geiger that I plan to start with -
>>> https://sourceforge.net/p/pure-data/patches/264/).
>>> Before doing that I want to do some reorganizing - in porting Pd to FreeRTOS
>>> (so I can run it on an Espressif LyraT board, which I think takes only about
>>> 10 or 20% of the current that a Pi needs) I found out that I had to move
>>> a few functions from one file to another.
>>> This might break some PRs, so... first of all would be to identify whatever
>>> PRs are ready to merge so I can do that before I make incompatible changes.
>>> Of course "stable development branch" first... then Dan's soundfile updates...
>>> then what?
>>> PS more ideas of mine (among many):
>>> hot-reloading externs via a message to Pd
>>> use a "unix binding" socket between Pd and pd-gui instead of localhost
>>> generalize number/symbol box to allow displaying entire messages or lists
>>> cheers
>>> Miller
>>> _______________________________________________
>>> Pd-dev mailing list
>>> Pd-dev at lists.iem.at
>>> https://lists.puredata.info/listinfo/pd-dev
>> 
>> 
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