Per Jessen said the following on 06/12/2012 09:22 AM:
Dave Howorth wrote:
Istvan Gabor wrote:
I have another question. Can the operation system/programs take advantage of multiple processors? Can one application use only one processor or more? Does this depend on the specific program or how the OS sorts tasks?
Yes, the operating system takes advantage of multiple processors (and cores and threads). Linux and Unix before it have been leaders in this area.
Let's not forget MVS and VM of course.
Indeed! Not other multi-processing OS from other vendors. And in its time, UNIX was a radical. All those other multi tasking OS of the 50s, 60 and through into the 70s (including DEC's VMS) had the idea of a fixed number of tasks preconfigured before boot when the OS setup was configured. What was it called? "sysgen" or something like that. Processes were deed to be "heavyweight" and then along came UNIX with lightweight, dynamically created processes that would vanish again once they were done. Just look: the shell created a print formatter that fed into the print driver and they came and went so fast that there was no reason to do the kind of process resource allocation and tuning that was such an essential facet of the management of mainframes. Damn it all! The shell was creating - forking off - light weight transient process that would do something, something pretty trivial, and die. Lets face it, the long lived programs we have today, database servers, firefox, thunderbird and more, are an effort to make Linux behave like the old mainframes; big, long lived, memory intensive applications that create their own internal "multiprogramming: with threading. Think CICS http://en.wikipedia.org/wiki/CICS#History Her must be some phrase analogous to "ontogeny recapitulates phylogeny" that applies here. -- Life is full of contradictions.... No it isn't. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org