> The fork() problem is due to memory registration aggravated by
> registration cache. Memory registration in itself is a hack from
> the OS
> point of view, and you already know a lot about the various problems
> related to registration cache.
So Gleb is indicating that this is a problem in the pipeline protocol
which does not use a registration cache. I think the registration
cache, while increasing the probability of badness after fork, is not
> The right way to fix the fork problem is to fix the memory
> problem in the OS itself. It's not going to happen anytime soon, so it
> requires another hack (forcing VM duplication of registered pages at
> fork time).
> Patrick Geoffray
> Myricom, Inc.
> devel mailing list