From: Markus Schöpflin (markus.schoepflin_at_[hidden])
Date: 2007-10-10 12:19:22
Ion Gaztañaga schrieb:
> Markus Schöpflin escribió:
>> Hello,
>>
>> this may be a silly question, but I have been wondering what the atomic
>> read and write primitives are actually supposed to do?
>>
>> I mean, from the readers or writers POV a read or write is always atomic,
>> isn't it? Am I missing something very obvious here?
>
> In some architectures, a 32 read might not be atomic (even if the read
> is aligned). I think that Intel system is always atomic. They are there
> for completeness, to support systems where read or write might not be
> atomic.
Sorry for being dense, but what exactly do you mean when you say a read
might not be atomic? Are you thinking of memory barriers here? Or is it
something else? Is there somewhere a definition of what atomic exactly
means here?
I'm asking because I'm currently evaluating how much of work it would be
to make interprocess work on Tru64.
Markus