Re: Removing kernel thread stack swapping

From: Ryan Sommers (ryans_at_gamersimpact.com)
Date: 03/03/05

  • Next message: David Xu: "Re: Removing kernel thread stack swapping" 
    Date: Thu, 03 Mar 2005 08:12:58 -0600
To: David Schultz <das@FreeBSD.ORG>

    David Schultz wrote:
    > Any objections to the idea of removing the feature of swapping out
    > kernel stacks? Unlike disabling UAREA swapping, this has the
    > small downside that it wastes 16K (give or take a power of 2) of
    > wired memory per kernel thread that we would otherwise have
    > swapped out. However, this disadvantage is probably negligible by
    > today's standards, and there are several advantages:

    I like the idea of fixing a lot of possible panics. However, I don't
    know if we should nix it completely. Wasting this little memory won't
    hurt anyone on a contemporary computer. However, our embedded systems
    folks don't look at memory in the same light, and 16K here or there can
    begin to really add up in a memory tight architecture. Of course it
    could be argued that embedded systems probably don't have many threads,
    many threads that can be swapped, or even swap space in the first place.

    I guess it's a judgment call that one of our embedded systems engineers
    could better answer. 

    -- 
Ryan Sommers
ryans@gamersimpact.com
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  • Next message: David Xu: "Re: Removing kernel thread stack swapping"

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