Re: Why OS takes so much memory?

From: Abdullah Ramazanoglu (abdullah_at_ramazanoglu.tr)
Date: 08/28/04

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    Date: Sun, 29 Aug 2004 00:58:14 +0300

    begin "Rinaldi J. Montessi" <rinaldi@Senior.Envision> dedi ki:
    > On Thu, 26 Aug 2004 19:23:54 -0000, Michael Heiming wrote:
    > [..]
    >>> total used free shared buffers cached
    >>> Mem: 3863200 2757620 1105580 0 532672 2079748
    >>> -/+ buffers/cache: 145200 3718000
    >> ^^^^^^^^^^^^^^^^^
    >>> Swap: 2048276 4888 2043388
    >>
    >> No it isn't used, only 145 MB are really used, the rest is used
    >> as (disk) cache/buffers and will be used for other things as soon
    >> as it is needed.
    >
    > Curious. Why would something be swapping?

    Because kernel VM management is so bright and greedy to utilize that last
    KB of RAM. When you run a system with a virtual memory footprint of -say-
    300M on a system with 4G RAM, some parts of this 300M is not used much.
    Then there is two choices for the kernel:
    1. Keep all of the 300M in RAM and use the rest (3.7G) for disk caching.
    2. Swap out stale parts of that 300M, reduce real memory footprint from
    300M to -say- 200M, and use the rest (3.8G) for disk caching.

    Apparently 2.6 kernel is smart to choose the 2nd option. 

    -- 
Abdullah        | aramazan@ |
Ramazanoglu     | myrealbox |
________________| D.0.T cöm |__
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