Re: Replacing a DTAQ with a USRQ

[Vern Hamberg <vhamberg@xxxxxxxxxxxxxxx>]

There is a manual for C/C++ that documents the MI functions that have 
been surfaced - for 7.4 it is at 
http://public.dhe.ibm.com/systems/power/docs/systemi/v6r1/en_US/sc092418.pdf 
- that manual has examples, yes, in C, but they are convertable. The 
functions you want are ENQ to write to the queue, DEQ to read from the 
queue. There is an API to create queues, as well, for which there is an 
example, also.

I think you can just use these functions in RPGLE - you don't need to 
specify a binding directory or the like - I might be wrong on that, so 
check it - I know we no longer need to do that with C/C++ library functions.

A challenge? Sure! A little! Barbara Morris has a document to help 
converting C prototypes to RPGLE, that'll be a great starting point for 
first-timers.

Good luck!
Vern

On 1/14/2022 2:20 PM, Bryan Dietz wrote:
> Carsten also has some examples.
>
> https://apimymymy.wordpress.com/?s=crtusrq
>
> Bryan
>
>
> Rich Loeber wrote on 1/14/2022 12:26 PM:
> > Alan,
> >
> > That would be very helpful.  I would love to see that code.
> >
> > Rich
> >
> > ________________________________
> >
> >
> > On 1/14/2022 1:21 PM, Alan Campin wrote:
> >
> > I have a service program that wraps functions for the user queue object
> > written in RPG.
> >
> > Actually writing to User Queues is a lot simpler in RPG than in C. 
> > They are
> > tough in C although there are a lot of examples out there using them 
> > in C.
> >
> > Let me know if you are interested.
> >
> > On Fri, Jan 14, 2022 at 10:06 AM Rich Loeber 
> > <rich@xxxxxxxxx><mailto:rich@xxxxxxxxx> wrote:
> >
> >
> >
> > According to IBM documentation, a USRQ will have better performance 
> > than a
> > DTAQ.  I have an application that is experiencing performance issues on
> > some customer systems and we now think that this is tied to a lot of 
> > data
> > going through a data queue.  Unfortunately, IBM documentation on how to
> > work with user queues is nearly nonexistent.  The only think I can 
> > find is
> > an example written in C which is of little use to us.  I see where 
> > you have
> > to use MI to read and write to a user queue and that doesn't scare us 
> > all
> > that much, but it would be good to know that diving into this project 
> > was
> > going to produce tangible results.
> >
> > Does anyone have any experience with user queues and have you done it 
> > in a
> > language other than C?  We need to be able to write to one and, in a
> > separate process, read from it all in FIFO sequence.
> >
> > Rich Loeber
> > Kisco Systems
> > http://www.kisco.com
> >
> > --
> > This is the Midrange Systems Technical Discussion (MIDRANGE-L) 
> > mailing list
> > To post a message email: 
> > MIDRANGE-L@xxxxxxxxxxxxxxxxxx<mailto:MIDRANGE-L@xxxxxxxxxxxxxxxxxx>
> > To subscribe, unsubscribe, or change list options,
> > visit: https://lists.midrange.com/mailman/listinfo/midrange-l
> > or email: 
> > MIDRANGE-L-request@xxxxxxxxxxxxxxxxxx<mailto:MIDRANGE-L-request@xxxxxxxxxxxxxxxxxx>
> > Before posting, please take a moment to review the archives
> > at https://archive.midrange.com/midrange-l.
> >
> > Please contact 
> > support@xxxxxxxxxxxxxxxxxxxx<mailto:support@xxxxxxxxxxxxxxxxxxxx> for 
> > any subscription related
> > questions.
> >
> > Help support midrange.com by shopping at amazon.com with our affiliate
> > link: https://amazon.midrange.com