[concurrency-interest] Atomic.*lazyGet

Vitaly Davidovich vitalyd at gmail.com
Wed Aug 8 09:32:15 EDT 2012


Doug, so what was the overwhelming reason for scrapping the Fences API? Is
it because the JMM would need a revision, as you mentioned? I'd think if
Fences was some "advanced" API with a caveat emptor that you need to know
what you're doing then it would be OK - or is that a can of worms you'd
rather not open?

Thanks

Sent from my phone
On Aug 8, 2012 9:26 AM, "Doug Lea" <dl at cs.oswego.edu> wrote:

> On 08/08/12 08:29, Aleksey Shipilev wrote:
>
>> Hi,
>>
>> Inspired by Doug's API completeness endeavor in CHM, and recent
>> WeakReference discussion, I had remembered the thing long haunting me.
>>
>> In short, I would like us to consider adding lazyGet() to our atomic
>> primitives. Googling around haven't got me to any pointers if anyone had
>> considered this before. If anyone had, please point me there.
>>
>
> See previous list discussions of "weakGet()" (which is a better name,
> in line with weakCompareAndSet), at least as far back as 2006.
> For example:
> http://cs.oswego.edu/**pipermail/concurrency-**
> interest/2006-May/002526.html<http://cs.oswego.edu/pipermail/concurrency-interest/2006-May/002526.html>
>
> I welcome Hans Boehm to summarize the reasons that we cannot
> do this without first overhauling the JMM spec.
> Well, we could do it, but if so, it would only have
> we-hope-you-know-what-we-mean semantics, which is
> not something most people are comfortable about for
> fundamental concurrency constructs. The lazySet case,
> that we did add without incorporation into JMM, was
> different in that we were confident that we could spec
> it formally without breaking things in a minor JMM revision
> when it came up next. For a sense of what this would look
> like, see near the end of the proposed/scrapped Fences javadoc
> http://gee.cs.oswego.edu/dl/**jsr166/dist/docs/java/util/**
> concurrent/atomic/Fences.html<http://gee.cs.oswego.edu/dl/jsr166/dist/docs/java/util/concurrent/atomic/Fences.html>
>
>
> -Doug
>
>
> ______________________________**_________________
> Concurrency-interest mailing list
> Concurrency-interest at cs.**oswego.edu <Concurrency-interest at cs.oswego.edu>
> http://cs.oswego.edu/mailman/**listinfo/concurrency-interest<http://cs.oswego.edu/mailman/listinfo/concurrency-interest>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://cs.oswego.edu/pipermail/concurrency-interest/attachments/20120808/cff6c098/attachment-0001.html>


More information about the Concurrency-interest mailing list