Back-pressure on xadd qs

[franz1981]

Xadd qs can check if there are free chunks available before performing an offer: it would enable a weak form of back-pressure depending on the configured pooled chunks.

Not sure If relaxedOffer is the right method to offer this, @nitsanw wdyt?

[nitsanw]

Is this to build some bounded capacity XADD queue? I need to dig deeper into the xadd queues before having this conversation I suspect :-)

[franz1981]

Is this to build some bounded capacity XADD queue?

Yep altough is less precise then what we have on other CAS-based queues: the queue is still unbounded, but is trying to stop offering if there is an high chance to not reuse chunks. Just a note: performance of this ATM are BAD, really BAD XD

I need to dig deeper into the xadd queues

That's my fault: I have changed them (especially mpmc) so many times that I haven't helped you to get a stable idea to work with :( Anyway feel free to ping me on hangout and we can arrange a chat: I believe that in max 30 minutes of chat can cover both :+1: