[dmd-concurrency] priority messages

[Andrei Alexandrescu]

Michel Fortin wrote:
> Le 2010-01-25 à 11:36, Kevin Bealer a écrit :
> 
>> Are you also considering multiple levels of priority?  In the
>> reader / processor / writer case, I can think of several priorities
>> the processor might want:
>> 
>> 1. Normal -- here is another buffer to write. 2. Medium -- the file
>> read failed, stop with this file. 3. Medium#2 -- too much
>> information too fast, please stop sending until further notice. 4.
>> High -- The system is going down, pack up and get out of dodge
>> 
>> I'm not sure if #2 and #3 need to be at different levels, but it
>> seems like 1, (2 or 3), and 4 should be distinct.  E.g. you don't
>> care about either Medium if there is a High in the pipe and you
>> want to process Normals after any High or Medium is handled.
>> 
>> This argues for a many-level approach, which might as well be an
>> integer or short.
> 
> I think only one queue where you can put messages directly on the
> front is enough.

I'm with Michel. Arbitrary priorities are a natural extension, but I 
don't want us to overengineer. Heck, I'd do without prioritySend if I 
could get away with it.

Andrei