[comp.parallel] RP3 memory management

lkaplan@BBN.COM (Larry Kaplan) (02/20/91)

In article <13202@hubcap.clemson.edu> tve%allspice.Berkeley.EDU@ucbvax.Berkeley.EDU (Thorsten von Eicken) writes:
>
>   I just read in an old ('85) paper that the RP3 supports interleaving
>of memory across processors and I wonder how this interacts with
>memory management (e.g. malloc or kernel-malloc).
> ....
>   My question now is how do you do memory allocation in this
>2-dimensional playground (Y-axis:local address, X-axis:processor)?
>Are there any papers published on this???

The RP3 interleaving scheme, and others including BBN's interleaving scheme,
allow the system to be configured so that only some of the memory is
interleaved.  This leads to having N+1 separate heaps for mallocs, one for
each memory (node) and one for interleaved memory.  Our approach has been to 
provide an extended malloc package for both the user and the kernel which 
allows the caller to ask for memory local to a specific node or interleaved 
memory.  Of course, this places a lot of burden on the programmer but then
he usually knows best.  

Some work has been done by various groups, e.g. Rochester and Duke, in trying 
to automatically handle the non-uniform memory management issues.  These don't 
generally address the use of interleaved memory though.

Hope this answers your question at least a little.
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