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Date: Sat, 15 Mar 2008 19:54:29 -1000 (HST)
From: Jeff Roberson <jroberson@chesapeake.net>
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To: Kip Macy <kip.macy@gmail.com>
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Cc: arch@freebsd.org
Subject: Re: separating out memory checks from INVARIANTS
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On Sat, 15 Mar 2008, Kip Macy wrote:

> I find that the serialization of memory allocation frequently hides
> race conditions. I would like to, at the very least, add an option to
> disable the memory checks if not make the memory checks a completely
> separate option. My knee jerk reaction to avoiding bikesheds is to
> simply add it to my own tree and forget about it. However, this has
> come up often enough that I feel that it warrants consideration.
>
>
> Thoughts?

One other option that I have frequently considered is to convert UMA from 
using an array of bytes to using bitfields to represent the free space in 
a slab.  Then you could use atomics to update the required information. 
It'd be a bit of work.  Maybe a good SoC? :)

Jeff

>
> -Kip
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