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

["Wiles, Keith" <keith.wiles@intel.com>]

> On Mar 10, 2017, at 9:35 PM, Kai Zhang <kay21s@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