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From: Colin Walters <walters@verbum.org>
To: Patches and discussions about the oe-core layer
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Date: Mon, 20 Feb 2012 09:05:00 -0500
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Subject: Re: Bitbake Memory Usage
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On Sat, 2012-02-18 at 23:36 +0000, Richard Purdie wrote:
> As soon as the child starts trying to remove
> things from memory, we lose the benefits of CoW and USS and PSS rise.

Note that even leaving out the garbage collector, the cPython VM
incrementing/decrementing the refcount of objects will force the copy.

The python multiprocessing module has some classes which allow
explicitly sharing memory.  Certainly for various caches e.g. if
they're just read-only after a certain point it might make sense
to wrap them in e.g. a multiprocessing.Value.