Re: [dpdk-users] Problem profiling DPDK

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

Sent from my iPhone

> On Jul 16, 2018, at 1:11 AM, 이지수 <skan1543@gmail.com> wrote:
> 
> Hi,
> 
> I have some issues with receiving 60bytes size packets without loss, so
> used perf tools to see what's happening.
> 
> I built DPDK and application which I'm using (DPDK-pktgen) with proper
> options for debugging (-g, O0) and here is my perf report's result.
> 
> 
> # Children      Self  Command        Shared Object      Symbol
>    89.16%     0.00%  lcore-slave-8  pktgen             [.] eal_thread_loop
>    89.16%     0.00%  lcore-slave-8  pktgen             [.]
> pktgen_launch_one_lcore
>    89.09%     0.66%  lcore-slave-8  pktgen             [.]
> pktgen_main_rxtx_loop
>    86.86%     2.43%  lcore-slave-8  pktgen             [.]
> pktgen_main_receive
>    47.08%    34.92%  lcore-slave-8  pktgen             [.] rte_pktmbuf_free
>    33.78%     5.77%  lcore-slave-8  pktgen             [.]
> pktgen_packet_classify_bulk
>    23.29%    11.15%  lcore-slave-8  pktgen             [.]
> pktgen_packet_classify
>    10.93%    10.89%  lcore-slave-8  pktgen             [.]
> i40e_recv_pkts_vec
>    10.84%     0.00%  lcore-slave-8  [unknown]          [.]
> 0x00303a3420205852
>    10.83%     0.00%  lcore-slave-8  [unknown]          [.]
> 0x00007f877d914680
>    10.52%    10.49%  lcore-slave-8  pktgen             [.]
> pktgen_packet_type
>     7.35%     3.05%  lcore-slave-8  pktgen             [.]
> rte_mbuf_refcnt_read
>     4.36%     4.35%  lcore-slave-8  pktgen             [.]
> rte_atomic16_read
>     4.35%     4.34%  lcore-slave-8  pktgen             [.] rte_prefetch0
>     3.32%     3.31%  lcore-slave-8  pktgen             [.]
> rte_memcpy_generic
> 
> I could see many readable symbols but there are two unknown symbols taking
> 10% at Children column.


These could be the calls to rte_manage_timer() as not much else is going on here for the code point of view. 

Notice the application is unknown and not pktgen so could be something in Linux. You can try vtune. 
> 
> Does anyone have ideas what these symbols are?
> 
> Thanks in advance.
> 
> Regards,
> 
> Jeesoo Lee