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

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

> On Feb 22, 2017, at 6:43 PM, Wiles, Keith <keith.wiles@intel.com> wrote:
> 
>> 
>> On Feb 22, 2017, at 6:30 PM, Sushil Adhikari <sushil446@gmail.com> wrote:
>> 
>> 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
> 
> What version of DPDK are you using? I was looking at the file at 1405 and I do not see a memset() call.

I found the memset call at 1142 in my 17.05-rc0 code. Please try the latest version and see if you get the same problem.

>> 
>> 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
>> 
>> 
> 
> Regards,
> Keith

Regards,
Keith