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

[Wiles, Keith]

> On Mar 11, 2017, at 9:45 AM, Kai Zhang <kay21s at gmail.com> wrote:
> 
> 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.

It would be nice to see both command lines. I am not sure I can help more all I can do is suggest some ideas to look at.

Does machine B have the same number and type of NICs? Use ‘lspci | grep Ethernet’ to get a list of all Ethernet devices on both machines.

What is the number of hugepages you have allocated for both machines.

Also look at the cpu_layout.py script to see why adding the 5th core would be different on the two machines and try to make them the same. 

> 
> 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
> 
> 

Regards,
Keith