Network RAM revisited
j.c.burton at gats-inc.com
Wed May 28 11:46:36 EDT 2003
Matt Phillips wrote:
> I guess the main argument against it is why not simply put in more
> memory sticks and avoid swap altogether. I was told there are
> applications out there that would still always need swap. To make the
> case more convincing, I would also like to test performance with real
> world application traces instead of probablity distributions. Does
> anyone know of applications (preferably used widespread) for which swap
> is unavoidable?
In my line of work (atmospheric remote sensing), its not so much a
matter of "applications for which swap is unavoidable", but "build it
and they will use it and more" - I don't care how "big" a machine /
cluster I build, the scientists will find a way to use all its resources
and ask for more. As I give them more powerful setups, their
mathematical models increase in size and complexity. Its a constant
battle to break even. Their models fill the existing memory and start
hitting swap, which slows their processing down. They need to run faster
so they can process a day's worth of data in one day, I give them more
memory. They fill up the additional memory and start hitting swap again,
but they need it to run faster so... (think you get the picture).
Swap allows them to continually improve / enhance their models.
Additional memory just makes it go faster.
Beowulf mailing list, Beowulf at beowulf.org
To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
More information about the Beowulf