Node de-staleifying thread

[shindavid]

David Wu wrote the following to me:

If I recall correctly, Leela Chess Zero's experimental implementations either included or discussed the possibility of including a special thread, whose job is not to do playouts at all and which never gets blocked on the GPU, it just wanders around the tree, de-staleifying nodes. There of course might be some implementation details too (e.g. ideally there could be some bookkeeping about what nodes that thread should be visiting rather than it just wandering randomly).

[nullhook]

is there a reference implementation of this?

[shindavid]

I am not aware of any. If David Wu's message to me was correct, then there may be an implementation of this in LC0, but I have not looked for it. (David Wu is the author of KataGo)