Re: Realtime Ada Conferences

[Ed Falis <falis@thomsoft.com>]

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Jeff T. Stevenson wrote:
> 
> 
> Is anything being done to allow Ada compiler vendors to
> produce compilers that have task context switch times
> in the 20 us range?  It seems that most compiler vendors
> are not able to comply with the Ada83 tasking model
> and provide realtime context switching capabilities.
> 

Jeff,

I think your info about context switching time is out of date.  Here's 
some sample PIWG data for our ActivAda Realtime product, an Ada 83 
compiler for 32 bit Intel x86 processors.  The benchmarks were run with 
checks on and optimizations on.  The target is a 75MHz 80486 DX4.

But like another person said, it's mostly a matter of processor speed, 
and this is certainly not the fastest thing we or others have.  The real 
issue is predictability.



-- 
Ed Falis	
Thomson Software   falis@thomsoft.com	(617) 221-7341
========================================================
Ideological disarmament: a koan for the 21st century
========================================================

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Test Name:   T000001                         Class Name:  Tasking
CPU Time:       19.59  MICROSECONDS          plus or minus      0.979
Wall/CPU:        1.00  ratio.                Iteration Count:   51200
Test Description:
 Minimum rendezvous, entry call and return time 
 1 task 1 entry , task inside procedure 
 no select 



Test Name:   T000002                         Class Name:  Tasking
CPU Time:       22.58  MICROSECONDS          plus or minus      1.129
Wall/CPU:        1.00  ratio.                Iteration Count:   51200
Test Description:
 Task entry call and return time measured
 One task active, one entry in task, task in a packae 
 no select statement 



Test Name:   T000003                         Class Name:  Tasking
CPU Time:       21.11  MICROSECONDS          plus or minus      1.056
Wall/CPU:        1.00  ratio.                Iteration Count:   51200
Test Description:
 Task entry call and return time measured
 Two tasks active, one entry per task, tasks in a package 
 no select statement 



Test Name:   T000004                         Class Name:  Tasking
CPU Time:       34.78  MICROSECONDS          plus or minus      1.739
Wall/CPU:        1.00  ratio.                Iteration Count:   51200
Test Description:
 Task entry call and return time measured
 One tasks active, two entries, tasks in a package 
 using select statement 



Test Name:   T000005                         Class Name:  Tasking
CPU Time:       23.30  MICROSECONDS          plus or minus      1.165
Wall/CPU:        1.00  ratio.                Iteration Count:   64000
Test Description:
 Task entry call and return time measured
 Ten tasks active, one entry per task, tasks in a package 
 no select statement 



Test Name:   T000006                         Class Name:  Tasking
CPU Time:       40.16  MICROSECONDS          plus or minus      2.008
Wall/CPU:        1.00  ratio.                Iteration Count:   32000
Test Description:
 Task entry call an return time measurement
 One task with ten entries , task in a package 
 one select statement, compare to T000005 



Test Name:   T000008                         Class Name:  Tasking
CPU Time:       53.87  MICROSECONDS          plus or minus      2.693
Wall/CPU:        1.00  ratio.                Iteration Count:   25600
Test Description:
 Measure the average time o pass an integer 
 from a producer task through a buffer task 
 to a consumer task