Re: numa_alloc_onnode does not allocate on node passed as argument

Hi Elena,

That would be great! I created a gist with the kernel config (cat /boot=
/config-$(uname -r)): https://gist.github.com/4tXJ7f/408a562abe5d4f2865=
6d

Please let me know if you need anything else.

Thank you very much,
Andres

> On 23 Oct 2014, at 06:15, Elena Ufimtseva <[email protected]> wrote=
:
>=20
> Hi Andres
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> I will poke around this on the weekend on my NUMA machine.
> Can you also attach your kernel config please?
>=20
> Thank you.
>=20
> On Wed, Oct 22, 2014 at 12:40 PM, Andres N=C3=B6tzli <noetzli@stanfor=
d.edu> wrote:
>> Hi Elena,
>>=20
>> Thank you very much for your quick reply! numa_set_strict(1) and num=
a_set_strict(0) both result in the wrong output. I did not change the d=
efault policy.
>>=20
>> numa_get_membind returns 1 for all nodes before and after numa_run_o=
n_node.
>> numa_get_interleave_mask returns 0 for all nodes.
>> numa_get_run_node_mask is all 1s before and 0010 after numa_run_on_n=
ode.
>>=20
>> The machine config (the CPUs are all Intel(R) Xeon(R) CPU E5-4657L v=
2 @ 2.40GHz):
>>=20
>> $ numactl --hardware
>> available: 4 nodes (0-3)
>> node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 48 49 50 51 52 53 54 55 56 57=
 58 59
>> node 0 size: 262093 MB
>> node 0 free: 966 MB
>> node 1 cpus: 12 13 14 15 16 17 18 19 20 21 22 23 60 61 62 63 64 65 6=
6 67 68 69 70 71
>> node 1 size: 262144 MB
>> node 1 free: 82 MB
>> node 2 cpus: 24 25 26 27 28 29 30 31 32 33 34 35 72 73 74 75 76 77 7=
8 79 80 81 82 83
>> node 2 size: 262144 MB
>> node 2 free: 102 MB
>> node 3 cpus: 36 37 38 39 40 41 42 43 44 45 46 47 84 85 86 87 88 89 9=
0 91 92 93 94 95
>> node 3 size: 262144 MB
>> node 3 free: 113 MB
>> node distances:
>> node   0   1   2   3
>>  0:  10  20  30  20
>>  1:  20  10  20  30
>>  2:  30  20  10  20
>>  3:  20  30  20  10
>>=20
>> Thanks again,
>> Andres
>>=20
>>> On 22 Oct 2014, at 06:12, Elena Ufimtseva <[email protected]> wro=
te:
>>>=20
>>> On Tue, Oct 21, 2014 at 11:47 PM, Andres N=C3=B6tzli <noetzli@stanf=
ord.edu> wrote:
>>>> Hi everyone,
>>>>=20
>>>> I am experiencing a weird problem. When using numa_alloc_onnode re=
peatedly to allocate memory, it does not allocate memory on the node pa=
ssed as an argument.
>>>>=20
>>>> Sample code:
>>>> #include <numa.h>
>>>> #include <numaif.h>
>>>> #include <iostream>
>>>> using namespace std;
>>>>=20
>>>> void find_memory_node_for_addr(void* ptr) {
>>>>  int numa_node =3D -1;
>>>>  if(get_mempolicy(&numa_node, NULL, 0, ptr, MPOL_F_NODE | MPOL_F_A=
DDR) < 0)
>>>>     cout << "WARNING: get_mempolicy failed" << endl;
>>>>  cout << numa_node << endl;
>>>> }
>>>>=20
>>>> int main() {
>>>>  int64_t* x;
>>>>  int64_t n =3D 5000;
>>>>  //numa_set_preferred(1);
>>>>=20
>>>>  numa_run_on_node(2);
>>>>  for(int i =3D 0; i < 20; i++) {
>>>>     size_t s =3D n * sizeof(int64_t);
>>>>     x =3D (int64_t*)numa_alloc_onnode(s, 1);
>>>>     for(int j =3D 0; j < n; j++)
>>>>        x[j] =3D j + i;
>>>>     find_memory_node_for_addr(x);
>>>>  }
>>>>=20
>>>>  return 0;
>>>> }
>>>>=20
>>>> Output:
>>>> 1
>>>> 1
>>>> 1
>>>> 2
>>>> 1
>>>> 2
>>>> 1
>>>> 2
>>>> 1
>>>> 2
>>>> 1
>>>> 2
>>>> 1
>>>> 2
>>>> 1
>>>> 2
>>>> 1
>>>> 2
>>>> 1
>>>> 2
>>>>=20
>>>> When uncommenting the line "numa_set_preferred(1);=E2=80=9D, the o=
utput is all 1s as expected. Am I doing something wrong? Have you seen =
similar issues?
>>>>=20
>>>> I am running Ubuntu 12.04.5 LTS:
>>>> $ cat /proc/version
>>>> Linux version 3.2.0-29-generic (buildd@allspice) (gcc version 4.6.=
3 (Ubuntu/Linaro 4.6.3-1ubuntu5) ) #46-Ubuntu SMP Fri Jul 27 17:03:23 U=
TC 2012
>>>>=20
>>>> I am using libnuma 2.0.10 but I=E2=80=99ve had the same problem wi=
th 2.0.8~rc3-1.
>>>>=20
>>>> Thank you very much,
>>>> Andres
>>>> --
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ma" in
>>>> the body of a message to [email protected]
>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>=20
>>> Hi Andres
>>>=20
>>> Can you try to use strict policy by calling numa_set_strict?
>>>=20
>>> If you comment out setting the preferred node, the default policy i=
s
>>> in action (I assume you did no change it, not for the process, not
>>> system wide) which is preferred also.
>>> But here you set preferred to a specific node and manual says, the
>>> default for process is to allocate on the node it runs.
>>> So I wonder what is the cpu affinity for this process looks like...
>>> Also maybe just to confirm you can check the policy from within you=
r
>>> running code?
>>>=20
>>> Can you also post the machine NUMA config?
>>>=20
>>> --
>>> Elena
>>=20
>>=20
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> --=20
> Elena