Re: Question about swap

[jeremy@sour.sw.oz.au (Jeremy Fitzhardinge) writes:]

>After looking at it for a few days, I still have a very simple
>sounding question: where does swap go?

Swap is done via the swap daemon. That is, the kernel thinks of swap as
a simple array 0..n of blocks, and sends requests to the swap daemon. The
swap daemon can maintain multiple swap device (see bin.src/test/swapd.c for
an example of how to tell him about new partitions) and send off I/O's to
their ultimate destination. He could also do remapping, allowing dynamic
expansion and contraction of the swap pool.

>... I have a linux swap partition on the same machine
>which could be shared, but I can't see how its done.

Our libdpart code appears to know about Linux swap. So the _lxswapX
partition from the disk server should work fine as the destination for swap.

Swapping is, ahem, "lightly" tested. If you start using it seriously you'll
probably have to chase some bugs. I got basic swapin/swapout working ages
ago, and haven't really hammered upon it since. I've been reviewing the
code of late and it still looks workable, but I'm sure there are still basic
bugs to be ironed out.

                                                Andy
Received on Tue Oct 18 07:11:14 1994