Implement "unordered channel" library site with the same ordering semantics as Orc publications

[arthurp]

The Orc standard library should have an "unordered channel" or "item pool" site which provides a channel with the same ordering guarentees as Orc publications (that is, almost none). This could be implemented much more efficiently than an ordered channel (using thread local queues and item stealing for instance) and it could be used in cases where publications are being tunneled around a trim or other combinator. In these cases the inputs are publications and the output is as publications as well so stronger ordering would be destroyed anyway.

• Decide on a name for the site. "Unordered channel" seems like an oxymoron and "item pool" is not clear. The site will act like a tuple space, except that it will not provide pattern matching support.
• Implement it using a concurrent pool of some sort in Scala. Consider using a split pool, but don't over do it. The big win for split pooling will come in a dOrc aware implementation.

[jthywiss]

I've used a wrapped Java ConcurrentHashMap for this a few times, so I concur with the need.

Name: How about just "Bag"?

[arthurp]

"Bag" is reasonable. I was thinking about a name that invokes the idea of "Tuple Space". Hmm.

[arthurp]

Looking back at this I'm concerned about the name "Bag" since I think this type should NOT support any kind of "contains" operations. It would only support get and put (and a few other related things) like channels. Allowing the user to look at the stored values without removing them would prevent some optimizations.

[jthywiss]

BlackBag? :-)

[arthurp]

What about "Pool" or "MessagePool"?