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SubjectRe: 128MB Swap-Space Limit
At 15:37 11/08/98 +0200, Thomas Scheunemann wrote:
>Is there any deeper reason, why a single swap-space is limited to 128MB (on

Note: this is from memory (and swapped back in, now).
Swapping is done by pages, 4KB at a time. A separate page of 4KB is used
by the kernel as a bitmap to describe the state of the various pages
inside the swap file. Such a bitmap contains 32K bits, each bit describing
the validity of a 4KB piece of the swapfile. Therefore, swapfiles are
limited to 32K*4KB = 128MB.

And yes, it's easy to enhance this. Either you keep more pages for your
swap bitmap or you activate more than one swapfile.
Not much difference, really.


Marnix Coppens

Reality is that which | Artificial Intelligence
when you stop believing | stands no chance against
in it doesn't go away. (Philip K. Dick) | Natural Stupidity.

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