Re: multi reads, single write

[Tom Payne <thp@roam-thp2.cs.ucr.edu>]

In comp.programming.threads Vladimir Olensky <vladimir_olensky@yahoo.com> wrote:

> Tom Payne wrote in message <833uh9$e4p$1@pravda.ucr.edu>...

[...]

>>Vladimir Olensky <vladimir_olensky@yahoo.com> wrote:
>>[...]
>>> My answer was exactly how to do that in a very simple and efficient
>>> way - using protected types in Ada that are specially designed for
>>> "multi-read single write" scenario in multithreaded/multitasking
>>> environment.
>>
>>Your answer does not, however, respond to the question of "what is the
>>most efficient way to implement" a CREW protocol.  It merely states
>>that all Ada implementations have a built-in implementation, which is
>>interesting but not particularly helpful.

[...]
> =============================================
> Some quotes from Ada ARM (9.1):
[...]
> Ada 95 protected objects are an amalgam of the best features
> of conditional critical regions and monitors: they collect all the
> data and operations together, like monitors, and yet they have
> barriers, like conditional critical regions. The barriers describe
> the required state that must exist before an operation can be
> performed in a clear manner which aids program proof and
> understanding. Protected objects are very similar to the shared
> objects of the Orca language developed by Bal, Kaashoek and
> Tanenbaum [Bal 92].

That's helpful and interesting, especially the last sentence.

Thanks,  ;-)

Tom Payne