swap sizing

[Bruce Evans]

On Mon, 30 May 2005, Ken Gunderson wrote:

> On larger systems sporting several gigs of ram, what it the recommended
> swap scheme?  I'm aware of the 2x ram rule of thumb and also that this
> rule is considered "old school" by many.

I don't use any except on machines with <= 64MB of RAM.

> And of course that you need
> at least as much swap as ram if you want to get a full dump...

Of course not.  The dump can be written to any disk device that you don't
care about overwriting.

> But other than that it seems we pretty much don't want/need to be
> swapping at all on modern machines.  Curious what folks are doing in the
> modern world with larger systems.

Swap is still needed if you run bloatware or lots of processes.  The only
significant differences between a machine with 3*N bytes of RAM and one
with N bytes of RAM and 2*N bytes of swap are that the former costs more
and is much faster if all of the allocated (RAM+swap) memory is actually
used.

Bruce