Re: Intel I210 (igb) sometimes consume all CPU on not-so-big traffic — need help!

[Michael Sierchio]

Is device polling enabled?

- M

On Thu, Nov 9, 2017 at 12:17 PM, Lev Serebryakov <lev at freebsd.org> wrote:

>
>  I still have problems with my E-1220v3 server equipped with Intel I210
> adapter. It can not be loaded more than 100Mbit/s because it is
> connection to internet.
>
>  But sometimes four interrupt threads "intr{irqXXX: igb0:que Y}" consume
> 100% CPU. Interrupt rate is very modest:
>
> % vmstat -i
> interrupt                          total       rate
> ...
> irq276: igb0:que 0             851899713       1193
> irq277: igb0:que 1             907338150       1271
> irq278: igb0:que 2             907538207       1271
> irq279: igb0:que 3             768217584       1076
> irq280: igb0:link                      2          0
> %
>
>  But CPU consumption is 90-100% per thread:
>
> PID USERNAME PRI NICE SIZE  RES STATE C   TIME   WCPU COMMAND
>  11 root     -92    -   0K 544K CPU2  2 146:22 98.30% intr{irq278:
> igb0:que 2}
>  11 root     -92    -   0K 544K WAIT  0 178:18 81.55% intr{irq276:
> igb0:que 0}
>  11 root     -92    -   0K 544K WAIT  1 135:34 77.77% intr{irq277:
> igb0:que 1}
>  11 root     -92    -   0K 544K CPU3  3 138:57 67.50% intr{irq279:
> igb0:que 3}
>
>  procstat -ak looks suspicious:
>
> % sudo procstat -ak | grep igb0:que
>    11 100056 intr   irq276: igb0:que 0  vm_page_scan_contig
> vm_phys_scan_contig vm_page_reclaim_contig kmem_alloc_contig
> mbuf_jumbo_alloc keg_alloc_slab keg_fetch_slab zone_fetch_slab
> zone_import zone_alloc_item uma_zalloc_arg m_getjcl igb_refresh_mbufs
> igb_rxeof igb_msix_que intr_event_execute_handlers ithread_loop fork_exit
>    11 100058 intr   irq277: igb0:que 1  mi_switch ithread_loop fork_exit
> fork_trampoline
>    11 100060 intr   irq278: igb0:que 2  mi_switch ithread_loop fork_exit
> fork_trampoline
>    11 100062 intr   irq279: igb0:que 3  mi_switch ithread_loop fork_exit
> fork_trampoline
> %
>
> --
> // Lev Serebryakov
>
>


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