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From: harold@harvax.UUCP (Harold Rabbie)
Subject: Senseless Bashing
Date: 21 Nov 89 01:35:24 GMT	[thread overview]
Message-ID: <8911210135.AA16930@monolith.RDYNET> (raw)

OK,  let's  get this issue out of the way regarding Ada tasking. Mr. Holden
states the following: 

>> Another article in the same issue describes the use of Ada in connection
>> with a real-time embedded digital signal processing application.  Since
>> Ada tasking could not be made fast enough for such work, the engineers
>> adapted a commercial run-time system, VRTX, and informed all programmers: 
 
>>      "Thou shalt not use Ada tasking, but rather VRTX tasking.
>>      "Thou shalt not use Ada dynamic memory allocation...
>>      "Thou shalt not use Ada generics; too slow...

'Tain't true that Ada tasking can't be made fast enough. How do you measure
speed?  You  can  buy  a  superset of VRTX called ARTX which implements Ada
tasking,  and, amazingly, it has the SAME context switch time for Ada tasks
as VRTX tasks. So it's not Ada tasking that's broken, it's just some of the
implementations. 

Also,  Ada  dynamic  memory allocation - there are implementations that are
slow, don't support UNCHECKED_DEALLOCATION, and raise STORAGE_ERROR just as
soon  as look at you. But then there are some that don't, and that give you
fixed  execution  time  for allocation and de-allocation. May the forces of
free-market capitalism prevail! 

Ada generics too slow? Most implementations that I'm aware of just spit out
multiple  copies  of  the  same code. Too large, maybe, but not too slow. I
never  understood  this belief that generics somehow aren't safe Ada. After
all,  they're  only glorified macros. Exceptions on the other hand ........
are just glorified GOTOs. 

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             reply	other threads:[~1989-11-21  1:35 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
1989-11-21  1:35 Harold Rabbie [this message]
  -- strict thread matches above, loose matches on Subject: below --
1989-11-20 14:33 Senseless Bashing CAROZZONI
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