Re: ten thousand small processes

From: Terry Lambert (tlambert2_at_mindspring.com)
Date: 06/27/03

  • Next message: Bakul Shah: "Re: ten thousand small processes" 
    Date: Fri, 27 Jun 2003 04:39:10 -0700
To: "D. J. Bernstein" <djb@cr.yp.to>

    "D. J. Bernstein" wrote:
    > Bakul Shah writes:
    > > Instead of complaining about wasting 78 megabytes and arguing
    > > about why various proposed solutions fall short and why your
    > > way is the best, why don't you come up with a patch that
    > > saves space for small programs?
    >
    > Funny. Seems to me that I keep making concrete suggestions---including a
    > detailed proposal for giving more space to malloc()---and the answer is
    > consistently ``We really don't care about per-process overhead.'' What's
    > the benefit of a patch for people who don't even see the problem?

    Your "concrete proposal for malloc" made a number of bad
    assumptions:

    o "UVA == 4G", rather than "UVA + KVA == 4G"

            Costs to move to "UVA == 4G":

            o pages must be mapped before each copy of
                    data across a protection domain
            o pages must be unmapped afterwards

    o If we had access to another 2G of UVA, we'd have no
            better use for it than to make malloc more space
            efficient

    My answer, at least, was "too computationally expensive for a
    general purpose OS when making the size/computational overhead
    tradeoff".

    -- Terry
    _______________________________________________
    freebsd-performance@freebsd.org mailing list
    http://lists.freebsd.org/mailman/listinfo/freebsd-performance
    To unsubscribe, send any mail to "freebsd-performance-unsubscribe@freebsd.org"

  • Next message: Bakul Shah: "Re: ten thousand small processes"

    Relevant Pages