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From: gshipman (gshipman_at_[hidden])
Date: 2007-05-17 14:40:06

> 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 culprit.

> The right way to fix the fork problem is to fix the memory
> registration
> 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
> --
> Patrick Geoffray
> Myricom, Inc.
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