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From "William A. Rowe, Jr." <>
Subject Re: Scoreboard API
Date Wed, 26 Aug 2009 02:29:03 GMT
Nick Kew wrote:
> I have a recollection of some discussion of providing a
> scoreboard API that would make it available to modules
> needing a chunk of shared memory.
> I'm in that position now, and my module needs to play
> with the scoreboard, as it creates additional children
> to be noted.  The easiest path is a one-off hack, in the
> manner of the loadbalancer stuff.  But if there's enough
> interest in a general API, that looks like a better
> approach in principle.
> Anyone have thoughts on the matter?  Shall I try and
> draft a general-purpose API?

Well, the original question was more oriented to additional-data-per-slot.
It should be fairly straightforward to allocate a shm to track children
(for example, mod_fcgid does this) but it seemed silly to create a whole
new shm for a handful of bytes per worker, when the data is worker oriented.

The API would have a few issues; it becomes impossible to gracefully
restart when adding the module; when removing the module the space must
still be fixed at its initial allocation.

If you want to create more "workers", that sounds outside the scope of this
initial thought, and more in line with mpm design, so your direction seems
like an extention to the mpm logic (if they will be 'workers' with

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