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Subject: Re: [hwloc-users] Thread core affinity
From: Gabriele Fatigati (g.fatigati_at_[hidden])
Date: 2011-08-01 09:04:24


Hi Brice,

you said:

"PU P#0" means "PU object with physical index 0".
"P#" prefix means "physical index".

But from the hwloc manual, page 58:

HWLOC_OBJ_PU: Processing Unit, or (Logical) Processor..

but it is in conflict with what you said :(

2011/8/1 Brice Goglin <Brice.Goglin_at_[hidden]>

> **
> "PU P#0" means "PU object with physical index 0".
> "P#" prefix means "physical index".
> "L#" prefix means "logical index" (the one you want to use in
> get_obj_by_type).
> Use -l or -p to switch from one to the other in lstopo.
>
> Brice
>
>
>
> Le 01/08/2011 14:47, Gabriele Fatigati a écrit :
>
> Hi Brice,
>
> so, if I inderstand well, PU P# numbers are not the same specified as
> HWLOC_OBJ_PU flag?
>
> 2011/8/1 Brice Goglin <Brice.Goglin_at_[hidden]>
>
>> Le 01/08/2011 12:16, Gabriele Fatigati a écrit :
>> > Hi,
>> >
>> > reading a hwloc-v1.2-a4 manual, on page 15, i look an example
>> > with 4-socket 2-core machine with hyperthreading.
>> >
>> > Core id's are not exclusive as said before. PU's id are exclusive but
>> > not physically sequential (I suppose)
>> >
>> > PU P#0 is in socket P#0 on Core P#0. PU P#1 is in another socket!
>>
>> These indexes are "physical indexes" (that's the default in the
>> graphical lstopo output). But we may want to make that clearer in the doc.
>>
>> Brice
>>
>>
>
>
> --
> Ing. Gabriele Fatigati
>
> Parallel programmer
>
> CINECA Systems & Tecnologies Department
>
> Supercomputing Group
>
> Via Magnanelli 6/3, Casalecchio di Reno (BO) Italy
>
> www.cineca.it Tel: +39 051 6171722
>
> g.fatigati [AT] cineca.it
>
>
>

-- 
Ing. Gabriele Fatigati
Parallel programmer
CINECA Systems & Tecnologies Department
Supercomputing Group
Via Magnanelli 6/3, Casalecchio di Reno (BO) Italy
www.cineca.it                    Tel:   +39 051 6171722
g.fatigati [AT] cineca.it