Messages in this thread | | | Subject | Re: WAY WAY OFFTOPIC: Message passing vs. shared memory (WAS: Re: 3.0 wishlist Was: Overview of 2.2.x goals?) | Date | Sun, 25 Jan 1998 10:31:38 -0800 | From | Stephen Williams <> |
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To throw fuel on the fire... :-)
voop@innocent.com said: > Which is better or worse of message passing or shared memory is a > matter of religion: the professors usually beat eachother up with > arguments for which is of preference.
A simple existence proof can show that message passing is computationally equivalent to shared memory w/ semaphores. algorithms tuned for each can be implemented with the other.
I've done very large distributed systems and find that message passing better reflects the distributed reality of large systems. When you start getting into error handling and faults, that memory doesn't normally have, you start to realize why communication protocols are described with messages.
DSHM is a neat idea, and should be provided by Linux, especially for the smaller problems, but the real nasty systems are going to be using some sort of message passing protocol.
-- Steve Williams "The woods are lovely, dark and deep. steve@icarus.com But I have promises to keep, steve@picturel.com and lines to code before I sleep, http://www.picturel.com And lines to code before I sleep."
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