Help performing timings

Help performing timings

[Simon Ibberson]

I am new to both Ada (4 weeks experience) and this newsgroup.

I need some help/information on how to perform some timings of Ada 
procedure calls, what I want to do is:

    Read the current time
    Make a procedure call
    Read the current time
    Calculate the elapsed time

I require very accurate timings, in the order of micro-seconds. 
Are there standard libraries for doing this?

Any help greatly appreciated, and replies by email if possible please
due to the current problems Demon are having with the news service.

-- 

Simon Ibberson

Re: Help performing timings

[Robert Dewar]

the best way to deal with this timing issue is to interface to appropriate
C routines in your library. There are no portable routines with this kind
of accuracy -- the closest you can come is to use the real time package
in the annex, but I think the easiest thing is just to interface directly
to the C routine, which is particularly easy in GNAT, since the standard
GNAT types correspond to the C types (e.g. int = Integer). Or, if you want
to be more "correct", use Interfaces.C types.

Re: Help performing timings

[Theodore Dennison]

si@lynx1.demon.co.uk (Simon Ibberson) wrote:
>I am new to both Ada (4 weeks experience) and this newsgroup.
>
>I need some help/information on how to perform some timings of Ada 
>procedure calls, what I want to do is:
>
>    Read the current time
>    Make a procedure call
>    Read the current time
>    Calculate the elapsed time
>
>I require very accurate timings, in the order of micro-seconds. 
>Are there standard libraries for doing this?

I will assume you mean Ada 83...

No. You will have to make system calls. The correct calls depand upon
what platform/OS/compiler you have.

However, it sounds to me like what you want is a performance analyzer.
Most good development systems come with one. They work much like a 
debugger, but merely log information and continue, rather than stopping
at their "trace points". Check you vendor/O.S. documentation to see
if you have one. Most come set up to automaticly collect data on the
amount of time spent in each routine/program block.

T.E.D. (strucutred programming mafioso)