Re: A question about task's select delay alternative

[reinert <reinkor@gmail.com>]

I have had some success using entries with barriers for avoiding bogging down the computer.

reinert

On Monday, April 23, 2018 at 8:25:39 PM UTC+2, NiGHTS wrote:
> On Monday, April 23, 2018 at 2:06:28 PM UTC-4, Jeffrey R. Carter wrote:
> > On 04/23/2018 07:32 PM, NiGHTS wrote:
> > > 
> > > What does "delay" actually do to the CPU? In this case I am using the Adacore GNAT compiler for a PC. Is it a loop constantly evaluating elapsed time? Or is it some kind of timed interrupt?
> > 
> > What timed selective accept "does to the CPU" is not defined by the language. 
> > It's determined by the compiler implementation and, probably, by the features of 
> > the OS, if any. So there's no Ada answer to your question.
> > 
> > I don't know how GNAT implements this, but my experience with it is that blocked 
> > tasks don't use significant CPU. You can test this easily enough.
> > 
> > Why do you care?
> > 
> > -- 
> > Jeff Carter
> > "When danger reared its ugly head, he bravely
> > turned his tail and fled."
> > Monty Python and the Holy Grail
> > 60
> 
> I have a number of busy threads I plan on launching, and I am wondering what cost I would incur launching them in parallel with watchdog threads. They are used to monitor the busy threads for performance faults and have fail alternatives if the threads take too long. 
> 
> I'd hate to bog down the CPU with unnecessary delays. Do I need to worry about lowering the CPU priority of such a non-essential thread in order to improve overall system performance?