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From: Adrian Chadd <adrian@freebsd.org>
To: Ian Lepore <freebsd@damnhippie.dyndns.org>
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Cc: freebsd-arm@freebsd.org, freebsd-mips@freebsd.org
Subject: Re: busdma buffer management enhancements - call for review and test
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I just want to make sure that you don't assume individual memory
access costs are the same regardless of how big the allocations are.

Ie, if you have a bunch of scattered L1-sized allocations, versus them
all being nearby in the same 512/1024 byte page; the underlying memory
architecture may be doing memory transactions at a slightly larger
size than your L1 assumption.

Damn these hierarchicial memory systems.


Adrian