On 09/27/2012 05:16 PM, m brandenberg wrote: > On Thu, 27 Sep 2012, David Coppa wrote: > >>> For starters, what is SSI? As many TLAs go, it can mean multiple >>> things. I won't try to guess what you want. >> >> Here's my guess: >> >> http://en.wikipedia.org/wiki/Single-system_image > > I... I... I can hear Theo's eyes roll from *3000* miles away! > > -- > Monty Brandenberg What problem is this "single image" intended to solve? There are better ways to do whatever it is.
There are research papers showing that the cost of transferring a process from machine to machine greatly exceeds the incremental increase in CPU availability. Sharing memory across a network, like threads, is almost always the wrong approach to data coherency. Sharing I/O devices across a network has mostly been accomplished, though NFS is a bad example. Synchronizing the mess is, in the general case, impossible. Basically, SSI is one of those traps (like threads, again) that might appeal to the naive but dies horribly once one really looks at the idea. Geoff Steckel
