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Subject: Re: [hwloc-devel] structure assumptions, duplication
From: Samuel Thibault (samuel.thibault_at_[hidden])
Date: 2009-09-29 13:08:53

Fawzi Mohamed, le Tue 29 Sep 2009 18:55:27 +0200, a écrit :
> cpuset -> cpuset_ptr (or just a flag that says if the structure has
> it, and thus two structures, a long one with it and a short one
> without, differing only in the tail if you really want to be hacky).
> Then cpuset is generated on the fly for the deepest level (like less
> than 4-8 proc -> lots of memory savings on large machines).
> (cost 1 function, and copying or building the cpuset)

Even for a machine with 1024 processors that amounts to just 128KB
saving. Even if you replicate it on each NUMA node, such nodes usually
have GBs of memory. Is it really worth spending efforts to save it? :)