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Subject: Re: [hwloc-users] Thread core affinity
From: Gabriele Fatigati (g.fatigati_at_[hidden])
Date: 2011-08-04 10:09:14


Ok,

but i dont' understand how lstopo works. Suppose on the physical die the
disposition of my cores non SMT) are like this:

    Socket:
        ______________
       | ____ ____ |
       | |*core* | |*core* | |
       | ____ ____ |
       | |*core* | |*core* | |
       | ____ ____ |
       | |*core* | |*core* | |
       | ______________|

lstopo how create the numerations? (sorry for the horrible figure). How the
numeration start? It consider physical OS index to list and create cores
topology? If yes, maybe Core L#0 and Core L#1 in a single socket are
physically near.

2011/8/4 Samuel Thibault <samuel.thibault_at_[hidden]>

> Gabriele Fatigati, le Thu 04 Aug 2011 15:52:09 +0200, a écrit :
> > how the topology gave by lstopo is built? In particolar, how the logical
> index
> > P# are initialized?
>
> P# are not logical indexes, they are physical indexes, as displayed in
> /proc/cpuinfo & such.
>
> The logical indexes, L#, displayed when passing the -l option to lstopo,
> are numbered simply linearly, after having sorted the PUs according to
> topology.
>
> Samuel
> _______________________________________________
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> hwloc-users_at_[hidden]
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>

-- 
Ing. Gabriele Fatigati
HPC specialist
SuperComputing Applications and Innovation Department
Via Magnanelli 6/3, Casalecchio di Reno (BO) Italy
www.cineca.it                    Tel:   +39 051 6171722
g.fatigati [AT] cineca.it