In normal parallel search in Crafty, when a thread goes "idle" it increments a counter, which is seen by all other threads. They can then initiate a split when they reach a point where they have satisfied the YBW criterion at a node. Why not do something similar over the net???
The distributed approach I am using is completely de-centralized so there is no single processor responsible
for allocating work, keeping info on other nodes etc . In short no place for counters whatsoever.
A processor doesnt even know if another processor is idle or not. All it does is send a "HELP" message and
wait for a "CANCEL" message (when that procesor is idle) or a "SPLIT" message ( when there is work to do ).
You are only thinking of SMP here so I will repeat here what I have mentioned before.
Imagine node A (with 2 threads) and node B are working at a split point. Node A and all its threads finished their
share of work and node B is still working. If node A just goes on working somewhere else who takes
care when node B returns with a "MERGE" message. It means A has to keep that old information and process it
accordingly while it is working somewhere else. This looks very inconvinient for me.You also can not tell
node B to take care of the split point when it is finished working. (I do exactly this in SMP btw)
Because when we send message to node B to do that it could have already finished its share of work
and already sent a "MERGE" message (only that we don't know about it yet because the message has not arrived here yet).
I don't consider the idea workable. You will have to make up your own mind. But don't just take my advice, or _anyone_ else's without giving the topic some thought. I'm not exactly new to parallel search and have formed my conclusions from testing 'em all. Our very first version of parallel Cray Blitz did _exactly_ this (split at root, unsynchronized). and it was _not_ very effective. It was better than just using one cpu, but not a lot better. True splitting approaches were not just superior, but _far_ superior.
Sure I can decide for myself what is good for me. I asked for other people's experience on it . You gave yours , GCP gave his ,so life goes on. Things do really get easily overheated in this forum though. Cheers