Re: [dpdk-users] Larger number of hugepages causes bus error.

[Sushil Adhikari <sushil446@gmail.com>]

I used the basic command line option "dpdkTimer -c 0xf -n 4"
And to update on my findings so far I have narrowed down to this line(1405)
memset(hugepage, 0, nr_hugefiles * sizeof(struct hugepage_file));
of function rte_eal_hugepage_init() in file
dpdk\lib\librte_eal\linuxapp\eal\eal_memory.c

Yes I have the hugepages of size 2MB(2048) and when I calculate the memory
this memset function is trying to set, it comes out to 512(nr_hugefiles) *
4144 ( sizeof(struct hugepage_file) ) = 2121728 which larger than 2MB, so
my doubt is that the hugepages I have allocated(512*2MB) is not contiguous
1GB memory its trying to access memory thats not part of hugepage, is that
a possibility, even though I am setting up hugepages during boot time by
providing it through kernel option.


On Wed, Feb 22, 2017 at 8:05 PM, Wiles, Keith <keith.wiles@intel.com> wrote:

>
> > On Feb 22, 2017, at 3:05 PM, Sushil Adhikari <sushil446@gmail.com>
> wrote:
> >
> > Hi,
> >
> > I was trying to run dpdk timer app by setting 512 2MB hugepages but the
> > application crashed with following error
> > EAL: Detected 4 lcore(s)
> > EAL: Probing VFIO support...
> > Bus error (core dumped)
> >
> > If I reduce the number of hugepages to 256 it works fine. I wondering
> what
> > could be the problem here. Here's my cpu info
>
> I normally run with 2048 x 2 or 2048 per socket on my machine. What is the
> command line you are using to start the application?
>
> >
> > processor       : 0
> > vendor_id       : GenuineIntel
> > cpu family      : 6
> > model           : 26
> > model name      : Intel(R) Core(TM) i7 CPU         950  @ 3.07GHz
> > stepping        : 5
> > microcode       : 0x11
> > cpu MHz         : 2794.000
> > cache size      : 8192 KB
> > physical id     : 0
> > siblings        : 4
> > core id         : 0
> > cpu cores       : 4
> > apicid          : 0
> > initial apicid  : 0
> > fpu             : yes
> > fpu_exception   : yes
> > cpuid level     : 11
> > wp              : yes
> > flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
> mca
> > cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx
> > rdtscp lm constant_tsc arch_
> > perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf pni
> dtes64
> > monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 popcnt
> > lahf_lm ida dtherm tpr_shadow vnm
> > i flexpriority ept vpid
> > bugs            :
> > bogomips        : 5600.00
> > clflush size    : 64
> > cache_alignment : 64
> > address sizes   : 36 bits physical, 48 bits virtual
> > power management:
> >
> > processor       : 1
> > vendor_id       : GenuineIntel
> > cpu family      : 6
> > model           : 26
> > model name      : Intel(R) Core(TM) i7 CPU         950  @ 3.07GHz
> > stepping        : 5
> > microcode       : 0x11
> > cpu MHz         : 2794.000
> > cache size      : 8192 KB
> > physical id     : 0
> > siblings        : 4
> > core id         : 1
> > cpu cores       : 4
> > apicid          : 2
> > initial apicid  : 2
> > fpu             : yes
> > fpu_exception   : yes
> > cpuid level     : 11
> > wp              : yes
> > flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
> mca
> > cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx
> > rdtscp lm constant_tsc arch_
> > perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf pni
> dtes64
> > monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 popcnt
> > lahf_lm ida dtherm tpr_shadow vnm
> > i flexpriority ept vpid
> > bugs            :
> > bogomips        : 5600.00
> > clflush size    : 64
> > cache_alignment : 64
> > address sizes   : 36 bits physical, 48 bits virtual
> > power management:......
> >
> > And Here's my meminfo
> >
> > MemTotal:       24679608 kB
> > MemFree:        24014156 kB
> > MemAvailable:   23950600 kB
> > Buffers:            3540 kB
> > Cached:            31436 kB
> > SwapCached:            0 kB
> > Active:            21980 kB
> > Inactive:          22256 kB
> > Active(anon):      10760 kB
> > Inactive(anon):     2940 kB
> > Active(file):      11220 kB
> > Inactive(file):    19316 kB
> > Unevictable:           0 kB
> > Mlocked:               0 kB
> > SwapTotal:             0 kB
> > SwapFree:              0 kB
> > Dirty:                32 kB
> > Writeback:             0 kB
> > AnonPages:          9252 kB
> > Mapped:            11912 kB
> > Shmem:              4448 kB
> > Slab:              27712 kB
> > SReclaimable:      11276 kB
> > SUnreclaim:        16436 kB
> > KernelStack:        2672 kB
> > PageTables:         1000 kB
> > NFS_Unstable:          0 kB
> > Bounce:                0 kB
> > WritebackTmp:          0 kB
> > CommitLimit:    12077660 kB
> > Committed_AS:     137792 kB
> > VmallocTotal:   34359738367 kB
> > VmallocUsed:           0 kB
> > VmallocChunk:          0 kB
> > HardwareCorrupted:     0 kB
> > AnonHugePages:      2048 kB
> > CmaTotal:              0 kB
> > CmaFree:               0 kB
> > HugePages_Total:     256
> > HugePages_Free:        0
> > HugePages_Rsvd:        0
> > HugePages_Surp:        0
> > Hugepagesize:       2048 kB
> > DirectMap4k:       22000 kB
> > DirectMap2M:    25133056 kB
>
> Regards,
> Keith
>
>