[dpdk-users] Issue with more Cores assigned: Cannot mmap device resource file

[Kai Zhang]

Hi Keith,

Thank you for your reply.

I have tested my program on two machines
A) 1 x Intel E5-2650 v4, 12 cores [UMA]
B) 2 x Intel E5-2640 v4, 10 cores [NUMA]

I am very sure that the primary process uses different cores with the
secondary process. The strange thing is that my program works correctly on
machine *B*. But on machine *A*, the above issue happens with more than 4
cores assigned to the secondary process.

I have tried to assign cores 1-5  to the secondary process and also
tried other core assignment policies, but the error still happens
rte_eal_init() with more than 4 cores.

Regards,
Kai

On Sat, Mar 11, 2017 at 10:52 PM, Wiles, Keith <keith.wiles at intel.com>
wrote:

>
> > On Mar 10, 2017, at 9:35 PM, Kai Zhang <kay21s at gmail.com> wrote:
> >
> > Hi, there
> >
> > I am using DPDK-16.11 on XL710 40GbE NIC. OS: CentOS 7.3.1611 with Linux
> > kernel version 3.8.0-30.
> >
> > I have a master process and a secondary process. When I run the secondary
> > process with less than or equal to 4 cores, it works correctly. Such as:
> > sudo ./program -l 4,5,6,7 -n 4 --proc-type=secondary
> > sudo ./program -c 0x0f -n 4 --proc-type=secondary
> >
> > However, there will be error in the rte_eal_init if I assign more than 4
> > cores.
> > sudo ./program -l 0,1,2,3,4 -n 4 --proc-type=secondary
> > sudo ./program -c 0x1f -n 4 --proc-type=secondary
> >
> > EAL: Cannot mmap device resource file
> > /sys/bus/pci/devices/0000:02:00.0/resource0 to address: 0x7fff65bfc000
> > EAL: Error - exiting with code: 1
> >  Cause: Requested device 0000:02:00.0 cannot be used
>
> I assume you have at least 8 cores. Have you tried -l 1-5 on the secondary
> process.
>
> You did not show the primary process command line, but the if you use 1-5
> then you can only give primary process -l 6-7 or two cores. It is always a
> reasonable thing is to leave core zero for linux to use.
>
> Also it could be you ran out of memory or hugepages you allocated to the
> system.
>
> >
> > Anyone knows why this happens?
> >
> > Thanks a lot,
> > Kai Zhang
>
> Regards,
> Keith
>
>