Marcin,

my understanding is that in this case, patched v1.10.1rc1 is working just
fine.
am I right ?

I prepared two patches
one to remove the warning when binding on one core if only one core is
available,
an other one to add a warning if the user asks a binding policy that makes
no sense with the required mapping policy

I will finalize them tomorrow hopefully

Cheers,

Gilles

On Tuesday, October 6, 2015, marcin.krotkiewski <
marcin.krotkiew...@gmail.com> wrote:

> Hi, Gilles
>
> you mentionned you had one failure with 1.10.1rc1 and -bind-to core
> could you please send the full details (script, allocation and output)
> in your slurm script, you can do
> srun -N $SLURM_NNODES -n $SLURM_NNODES --cpu_bind=none -l grep
> Cpus_allowed_list /proc/self/status
> before invoking mpirun
>
> It was an interactive job allocated with
>
> salloc --account=staff --ntasks=32 --mem-per-cpu=2G --time=120:0:0
>
> The slurm environment is the following
>
> SLURM_JOBID=12714491
> SLURM_JOB_CPUS_PER_NODE='4,2,5(x2),4,7,5'
> SLURM_JOB_ID=12714491
> SLURM_JOB_NODELIST='c1-[2,4,8,13,16,23,26]'
> SLURM_JOB_NUM_NODES=7
> SLURM_JOB_PARTITION=normal
> SLURM_MEM_PER_CPU=2048
> SLURM_NNODES=7
> SLURM_NODELIST='c1-[2,4,8,13,16,23,26]'
> SLURM_NODE_ALIASES='(null)'
> SLURM_NPROCS=32
> SLURM_NTASKS=32
> SLURM_SUBMIT_DIR=/cluster/home/marcink
> SLURM_SUBMIT_HOST=login-0-1.local
> SLURM_TASKS_PER_NODE='4,2,5(x2),4,7,5'
>
> The output of the command you asked for is
>
> 0: c1-2.local  Cpus_allowed_list:        1-4,17-20
> 1: c1-4.local  Cpus_allowed_list:        1,15,17,31
> 2: c1-8.local  Cpus_allowed_list:        0,5,9,13-14,16,21,25,29-30
> 3: c1-13.local  Cpus_allowed_list:       3-7,19-23
> 4: c1-16.local  Cpus_allowed_list:       12-15,28-31
> 5: c1-23.local  Cpus_allowed_list:       2-4,8,13-15,18-20,24,29-31
> 6: c1-26.local  Cpus_allowed_list:       1,6,11,13,15,17,22,27,29,31
>
> Running with command
>
> mpirun --mca rmaps_base_verbose 10 --hetero-nodes --bind-to core
> --report-bindings --map-by socket -np 32 ./affinity
>
> I have attached two output files: one for the original 1.10.1rc1, one for
> the patched version.
>
> When I said 'failed in one case' I was not precise. I got an error on node
> c1-8, which was the first one to have different number of MPI processes on
> the two sockets. It would also fail on some later nodes, just that because
> of the error we never got there.
>
> Let me know if you need more.
>
> Marcin
>
>
>
>
>
>
>
> Cheers,
>
> Gilles
>
> On 10/4/2015 11:55 PM, marcin.krotkiewski wrote:
>
> Hi, all,
>
> I played a bit more and it seems that the problem results from
>
> trg_obj = opal_hwloc_base_find_min_bound_target_under_obj()
>
> called in rmaps_base_binding.c / bind_downwards being wrong. I do not know
> the reason, but I think I know when the problem happens (at least on
> 1.10.1rc1). It seems that by default openmpi maps by socket. The error
> happens when for a given compute node there is a different number of cores
> used on each socket. Consider previously studied case (the debug outputs I
> sent in last post). c1-8, which was source of error, has 5 mpi processes
> assigned, and the cpuset is the following:
>
> 0, 5, 9, 13, 14, 16, 21, 25, 29, 30
>
> Cores 0,5 are on socket 0, cores 9, 13, 14 are on socket 1. Binding
> progresses correctly up to and including core 13 (see end of file
> out.1.10.1rc2, before the error). That is 2 cores on socket 0, and 2 cores
> on socket 1. Error is thrown when core 14 should be bound - extra core on
> socket 1 with no corresponding core on socket 0. At that point the returned
> trg_obj points to the first core on the node (os_index 0, socket 0).
>
> I have submitted a few other jobs and I always had an error in such
> situation. Moreover, if I now use --map-by core instead of socket, the
> error is gone, and I get my expected binding:
>
> rank 0 @ compute-1-2.local  1, 17,
> rank 1 @ compute-1-2.local  2, 18,
> rank 2 @ compute-1-2.local  3, 19,
> rank 3 @ compute-1-2.local  4, 20,
> rank 4 @ compute-1-4.local  1, 17,
> rank 5 @ compute-1-4.local  15, 31,
> rank 6 @ compute-1-8.local  0, 16,
> rank 7 @ compute-1-8.local  5, 21,
> rank 8 @ compute-1-8.local  9, 25,
> rank 9 @ compute-1-8.local  13, 29,
> rank 10 @ compute-1-8.local  14, 30,
> rank 11 @ compute-1-13.local  3, 19,
> rank 12 @ compute-1-13.local  4, 20,
> rank 13 @ compute-1-13.local  5, 21,
> rank 14 @ compute-1-13.local  6, 22,
> rank 15 @ compute-1-13.local  7, 23,
> rank 16 @ compute-1-16.local  12, 28,
> rank 17 @ compute-1-16.local  13, 29,
> rank 18 @ compute-1-16.local  14, 30,
> rank 19 @ compute-1-16.local  15, 31,
> rank 20 @ compute-1-23.local  2, 18,
> rank 29 @ compute-1-26.local  11, 27,
> rank 21 @ compute-1-23.local  3, 19,
> rank 30 @ compute-1-26.local  13, 29,
> rank 22 @ compute-1-23.local  4, 20,
> rank 31 @ compute-1-26.local  15, 31,
> rank 23 @ compute-1-23.local  8, 24,
> rank 27 @ compute-1-26.local  1, 17,
> rank 24 @ compute-1-23.local  13, 29,
> rank 28 @ compute-1-26.local  6, 22,
> rank 25 @ compute-1-23.local  14, 30,
> rank 26 @ compute-1-23.local  15, 31,
>
> Using --map-by core seems to fix the issue on 1.8.8, 1.10.0 and 1.10.1rc1.
> However, there is still a difference in behavior between 1.10.1rc1 and
> earlier versions. In the SLURM job described in last post, 1.10.1rc1 fails
> to bind only in 1 case, while the earlier versions fail in 21 out of 32
> cases. You mentioned there was a bug in hwloc. Not sure if it can explain
> the difference in behavior.
>
> Hope this helps to nail this down.
>
> Marcin
>
>
>
>
> On 10/04/2015 09:55 AM, Gilles Gouaillardet wrote:
>
> Ralph,
>
> I suspect ompi tries to bind to threads outside the cpuset.
> this could be pretty similar to a previous issue when ompi tried to bind
> to cores outside the cpuset.
> /* when a core has more than one thread, would ompi assume all the threads
> are available if the core is available ? */
> I will investigate this from tomorrow
>
> Cheers,
>
> Gilles
>
> On Sunday, October 4, 2015, Ralph Castain <
> <javascript:_e(%7B%7D,'cvml','r...@open-mpi.org');>r...@open-mpi.org
> <javascript:_e(%7B%7D,'cvml','r...@open-mpi.org');>> wrote:
>
>> Thanks - please go ahead and release that allocation as I’m not going to
>> get to this immediately. I’ve got several hot irons in the fire right now,
>> and I’m not sure when I’ll get a chance to track this down.
>>
>> Gilles or anyone else who might have time - feel free to take a gander
>> and see if something pops out at you.
>>
>> Ralph
>>
>>
>> On Oct 3, 2015, at 11:05 AM, marcin.krotkiewski <
>> marcin.krotkiew...@gmail.com> wrote:
>>
>>
>> Done. I have compiled 1.10.0 and 1.10.rc1 with --enable-debug and executed
>>
>> mpirun --mca rmaps_base_verbose 10 --hetero-nodes --report-bindings
>> --bind-to core -np 32 ./affinity
>>
>> In case of 1.10.rc1 I have also added :overload-allowed - output in a
>> separate file. This option did not make much difference for 1.10.0, so I
>> did not attach it here.
>>
>> First thing I noted for 1.10.0 are lines like
>>
>> [login-0-1.local:03399] [[37945,0],0] GOT 1 CPUS
>> [login-0-1.local:03399] [[37945,0],0] PROC [[37945,1],27] BITMAP
>> [login-0-1.local:03399] [[37945,0],0] PROC [[37945,1],27] ON c1-26 IS NOT
>> BOUND
>>
>> with an empty BITMAP.
>>
>> The SLURM environment is
>>
>> set | grep SLURM
>> SLURM_JOBID=12714491
>> SLURM_JOB_CPUS_PER_NODE='4,2,5(x2),4,7,5'
>> SLURM_JOB_ID=12714491
>> SLURM_JOB_NODELIST='c1-[2,4,8,13,16,23,26]'
>> SLURM_JOB_NUM_NODES=7
>> SLURM_JOB_PARTITION=normal
>> SLURM_MEM_PER_CPU=2048
>> SLURM_NNODES=7
>> SLURM_NODELIST='c1-[2,4,8,13,16,23,26]'
>> SLURM_NODE_ALIASES='(null)'
>> SLURM_NPROCS=32
>> SLURM_NTASKS=32
>> SLURM_SUBMIT_DIR=/cluster/home/marcink
>> SLURM_SUBMIT_HOST=login-0-1.local
>> SLURM_TASKS_PER_NODE='4,2,5(x2),4,7,5'
>>
>> I have submitted an interactive job on screen for 120 hours now to work
>> with one example, and not change it for every post :)
>>
>> If you need anything else, let me know. I could introduce some
>> patch/printfs and recompile, if you need it.
>>
>> Marcin
>>
>>
>>
>> On 10/03/2015 07:17 PM, Ralph Castain wrote:
>>
>> Rats - just realized I have no way to test this as none of the machines I
>> can access are setup for cgroup-based multi-tenant. Is this a debug version
>> of OMPI? If not, can you rebuild OMPI with —enable-debug?
>>
>> Then please run it with —mca rmaps_base_verbose 10 and pass along the
>> output.
>>
>> Thanks
>> Ralph
>>
>>
>> On Oct 3, 2015, at 10:09 AM, Ralph Castain <r...@open-mpi.org
>> <javascript:_e(%7B%7D,'cvml','r...@open-mpi.org');>> wrote:
>>
>> What version of slurm is this? I might try to debug it here. I’m not sure
>> where the problem lies just yet.
>>
>>
>> On Oct 3, 2015, at 8:59 AM, marcin.krotkiewski <
>> <javascript:_e(%7B%7D,'cvml','marcin.krotkiew...@gmail.com');>
>> marcin.krotkiew...@gmail.com
>> <javascript:_e(%7B%7D,'cvml','marcin.krotkiew...@gmail.com');>> wrote:
>>
>> Here is the output of lstopo. In short, (0,16) are core 0, (1,17) - core
>> 1 etc.
>>
>> Machine (64GB)
>>   NUMANode L#0 (P#0 32GB)
>>     Socket L#0 + L3 L#0 (20MB)
>>       L2 L#0 (256KB) + L1d L#0 (32KB) + L1i L#0 (32KB) + Core L#0
>>         PU L#0 (P#0)
>>         PU L#1 (P#16)
>>       L2 L#1 (256KB) + L1d L#1 (32KB) + L1i L#1 (32KB) + Core L#1
>>         PU L#2 (P#1)
>>         PU L#3 (P#17)
>>       L2 L#2 (256KB) + L1d L#2 (32KB) + L1i L#2 (32KB) + Core L#2
>>         PU L#4 (P#2)
>>         PU L#5 (P#18)
>>       L2 L#3 (256KB) + L1d L#3 (32KB) + L1i L#3 (32KB) + Core L#3
>>         PU L#6 (P#3)
>>         PU L#7 (P#19)
>>       L2 L#4 (256KB) + L1d L#4 (32KB) + L1i L#4 (32KB) + Core L#4
>>         PU L#8 (P#4)
>>         PU L#9 (P#20)
>>       L2 L#5 (256KB) + L1d L#5 (32KB) + L1i L#5 (32KB) + Core L#5
>>         PU L#10 (P#5)
>>         PU L#11 (P#21)
>>       L2 L#6 (256KB) + L1d L#6 (32KB) + L1i L#6 (32KB) + Core L#6
>>         PU L#12 (P#6)
>>         PU L#13 (P#22)
>>       L2 L#7 (256KB) + L1d L#7 (32KB) + L1i L#7 (32KB) + Core L#7
>>         PU L#14 (P#7)
>>         PU L#15 (P#23)
>>     HostBridge L#0
>>       PCIBridge
>>         PCI 8086:1521
>>           Net L#0 "eth0"
>>         PCI 8086:1521
>>           Net L#1 "eth1"
>>       PCIBridge
>>         PCI 15b3:1003
>>           Net L#2 "ib0"
>>           OpenFabrics L#3 "mlx4_0"
>>       PCIBridge
>>         PCI 102b:0532
>>       PCI 8086:1d02
>>         Block L#4 "sda"
>>   NUMANode L#1 (P#1 32GB) + Socket L#1 + L3 L#1 (20MB)
>>     L2 L#8 (256KB) + L1d L#8 (32KB) + L1i L#8 (32KB) + Core L#8
>>       PU L#16 (P#8)
>>       PU L#17 (P#24)
>>     L2 L#9 (256KB) + L1d L#9 (32KB) + L1i L#9 (32KB) + Core L#9
>>       PU L#18 (P#9)
>>       PU L#19 (P#25)
>>     L2 L#10 (256KB) + L1d L#10 (32KB) + L1i L#10 (32KB) + Core L#10
>>       PU L#20 (P#10)
>>       PU L#21 (P#26)
>>     L2 L#11 (256KB) + L1d L#11 (32KB) + L1i L#11 (32KB) + Core L#11
>>       PU L#22 (P#11)
>>       PU L#23 (P#27)
>>     L2 L#12 (256KB) + L1d L#12 (32KB) + L1i L#12 (32KB) + Core L#12
>>       PU L#24 (P#12)
>>       PU L#25 (P#28)
>>     L2 L#13 (256KB) + L1d L#13 (32KB) + L1i L#13 (32KB) + Core L#13
>>       PU L#26 (P#13)
>>       PU L#27 (P#29)
>>     L2 L#14 (256KB) + L1d L#14 (32KB) + L1i L#14 (32KB) + Core L#14
>>       PU L#28 (P#14)
>>       PU L#29 (P#30)
>>     L2 L#15 (256KB) + L1d L#15 (32KB) + L1i L#15 (32KB) + Core L#15
>>       PU L#30 (P#15)
>>       PU L#31 (P#31)
>>
>>
>>
>> On 10/03/2015 05:46 PM, Ralph Castain wrote:
>>
>> Maybe I’m just misreading your HT map - that slurm nodelist syntax is a
>> new one to me, but they tend to change things around. Could you run lstopo
>> on one of those compute nodes and send the output?
>>
>> I’m just suspicious because I’m not seeing a clear pairing of HT numbers
>> in your output, but HT numbering is BIOS-specific and I may just not be
>> understanding your particular pattern. Our error message is clearly
>> indicating that we are seeing individual HTs (and not complete cores)
>> assigned, and I don’t know the source of that confusion.
>>
>>
>> On Oct 3, 2015, at 8:28 AM, marcin.krotkiewski <
>> <javascript:_e(%7B%7D,'cvml','marcin.krotkiew...@gmail.com');>
>> marcin.krotkiew...@gmail.com
>> <javascript:_e(%7B%7D,'cvml','marcin.krotkiew...@gmail.com');>> wrote:
>>
>>
>> On 10/03/2015 04:38 PM, Ralph Castain wrote:
>>
>> If mpirun isn’t trying to do any binding, then you will of course get the
>> right mapping as we’ll just inherit whatever we received.
>>
>> Yes. I meant that whatever you received (what SLURM gives) is a correct
>> cpu map and assigns _whole_ CPUs, not a single HT to MPI processes. In the
>> case mentioned earlier openmpi should start 6 tasks on c1-30. If HT would
>> be treated as separate and independent cores, sched_getaffinity of an MPI
>> process started on c1-30 would return a map with 6 entries only. In my case
>> it returns a map with 12 entries - 2 for each core. So one  process is in
>> fact allocated both HTs, not only one. Is what I'm saying correct?
>>
>> Looking at your output, it’s pretty clear that you are getting
>> independent HTs assigned and not full cores.
>>
>> How do you mean? Is the above understanding wrong? I would expect that on
>> c1-30 with --bind-to core openmpi should bind to logical cores 0 and 16
>> (rank 0), 1 and 17 (rank 2) and so on. All those logical cores are
>> available in sched_getaffinity map, and there is twice as many logical
>> cores as there are MPI processes started on the node.
>>
>> My guess is that something in slurm has changed such that it detects that
>> HT has been enabled, and then begins treating the HTs as completely
>> independent cpus.
>>
>> Try changing “-bind-to core” to “-bind-to hwthread  -use-hwthread-cpus”
>> and see if that works
>>
>> I have and the binding is wrong. For example, I got this output
>>
>> rank 0 @ compute-1-30.local  0,
>> rank 1 @ compute-1-30.local  16,
>>
>> Which means that two ranks have been bound to the same physical core
>> (logical cores 0 and 16 are two HTs of the same core). If I use --bind-to
>> core, I get the following correct binding
>>
>> rank 0 @ compute-1-30.local  0, 16,
>>
>> The problem is many other ranks get bad binding with 'rank XXX is not
>> bound (or bound to all available processors)' warning.
>>
>> But I think I was not entirely correct saying that 1.10.1rc1 did not fix
>> things. It still might have improved something, but not everything.
>> Consider this job:
>>
>> SLURM_JOB_CPUS_PER_NODE='5,4,6,5(x2),7,5,9,5,7,6'
>> SLURM_JOB_NODELIST='c8-[31,34],c9-[30-32,35-36],c10-[31-34]'
>>
>> If I run 32 tasks as follows (with 1.10.1rc1)
>>
>> mpirun --hetero-nodes --report-bindings --bind-to core -np 32 ./affinity
>>
>> I get the following error:
>>
>> --------------------------------------------------------------------------
>> A request was made to bind to that would result in binding more
>> processes than cpus on a resource:
>>
>>    Bind to:     CORE
>>    Node:        c9-31
>>    #processes:  2
>>    #cpus:       1
>>
>> You can override this protection by adding the "overload-allowed"
>> option to your binding directive.
>> --------------------------------------------------------------------------
>>
>>
>> If I now use --bind-to core:overload-allowed, then openmpi starts and
>> _most_ of the threads are bound correctly (i.e., map contains two logical
>> cores in ALL cases), except this case that required the overload flag:
>>
>> rank 15 @ compute-9-31.local   1, 17,
>> rank 16 @ compute-9-31.local  11, 27,
>> rank 17 @ compute-9-31.local   2, 18,
>> rank 18 @ compute-9-31.local  12, 28,
>> rank 19 @ compute-9-31.local   1, 17,
>>
>> Note pair 1,17 is used twice. The original SLURM delivered map (no
>> binding) on this node is
>>
>> rank 15 @ compute-9-31.local  1, 2, 11, 12, 13, 17, 18, 27, 28, 29,
>> rank 16 @ compute-9-31.local  1, 2, 11, 12, 13, 17, 18, 27, 28, 29,
>> rank 17 @ compute-9-31.local  1, 2, 11, 12, 13, 17, 18, 27, 28, 29,
>> rank 18 @ compute-9-31.local  1, 2, 11, 12, 13, 17, 18, 27, 28, 29,
>> rank 19 @ compute-9-31.local  1, 2, 11, 12, 13, 17, 18, 27, 28, 29,
>>
>> Why does openmpi use cores (1,17) twice instead of using core (13,29)?
>> Clearly, the original SLURM-delivered map has 5 CPUs included, enough for 5
>> MPI processes.
>>
>> Cheers,
>>
>> Marcin
>>
>>
>>
>> On Oct 3, 2015, at 7:12 AM, marcin.krotkiewski <
>> <javascript:_e(%7B%7D,'cvml','marcin.krotkiew...@gmail.com');>
>> marcin.krotkiew...@gmail.com
>> <javascript:_e(%7B%7D,'cvml','marcin.krotkiew...@gmail.com');>> wrote:
>>
>>
>> On 10/03/2015 01:06 PM, Ralph Castain wrote:
>>
>> Thanks Marcin. Looking at this, I’m guessing that Slurm may be treating
>> HTs as “cores” - i.e., as independent cpus. Any chance that is true?
>>
>> Not to the best of my knowledge, and at least not intentionally. SLURM
>> starts as many processes as there are physical cores, not threads. To
>> verify this, consider this test case:
>>
>>
>
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