Re: Rationale: No New OS.

Dan Clemmensen (
Sun, 22 Nov 1998 10:59:58 -0500

Eliezer S. Yudkowsky wrote:
> If you need an OS to do something, rewrite Linux.
> And hasn't Beowolf done distributed supercomputing already?
Actually, Beowulf is a set of Linux extensions that permit disributed supercomputing of the traditional kind in which the applicatons are specifically written to use the beowulf infrastructure. It's very impressive in the traditional supercomputing domain. There is another linux extension effort that I find more interesting: Mosix. The Mosix extensions allow a cluster to loadshare at the task level, without the applications needing to know about the infrastructure. If all the computers on the internet were running Mosix, in theory any time a task was spawned or suspended anywhere, it could migrate anywhere else to execute. In practice, task migration decision algorithms are "non-trivial", so such a large Mosix would certainly fail as the coordination bandwidth usage exceeds the effective gain in CPU utilization. However, these algorithma are amenable to optimization. The exciting current work is for large locally-connected clusters, so less is being done for internet-connected migration algorithms. We know that some distributed algorithms work well even with very poor connectivity: look at the Mersenne prime or DES cracking efforts. At the other end of the scale, Some tasks have such a high intertask bandwidth that it is essentially infeasible to run them in separate menories.