Re: [dpdk-dev] drops while transmitting to the kni using rte_kni_tx_burst()

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 1/16/2017 2:47 PM, Shirley Avishour wrote:
> Hi,
> As I wrote the kernel thread runs on a dedicated lcore.
> running top while my application is running I see kni_single and the cpu
> usage is really low...
> Is there any rate limitation for transmitting to the kernel interface
> (since packets are being copied in the kernel).

Yes, kind of, kernel thread sleeps periodically, with a value defined by
KNI_KTHREAD_RESCHEDULE_INTERVAL. You can try tweaking this value, if you
want thread do more work, less sleep J

Also KNI_RX_LOOP_NUM can be updated for same purpose.

> 
> 
> On Mon, Jan 16, 2017 at 4:42 PM, Ferruh Yigit <ferruh.yigit@intel.com
> <mailto:ferruh.yigit@intel.com>> wrote:
> 
>     On 1/16/2017 12:20 PM, Shirley Avishour wrote:
>     > Hi,
>     > I have an application over dpdk which is consisted of the following threads
>     > each running on a separate core:
>     > 1) rx thread which listens on in a poll mode for traffic
>     > 2) 2 packet processing threads (for load balancing)
>     > 3) kni thread (which also runs on a separate core).
> 
>     This is kernel thread, right? Is it bind to any specific core?
>     Is it possible that this thread shares the core with 2nd processing
>     thread when enabled?
> 
>     >
>     > the rx thread receives packets and clones them and transmit a copy
>     to the
>     > kni and the other packet is sent to the packet processing unit
>     (hashing
>     > over 2 threads).
>     > the receive traffic rate is 100Mbps.
>     > When working with single packet processing thread I am able to get
>     all the
>     > 100Mbps towards the kni with no drops.
>     > but when I activate my application with 2 packet processing
>     threads I start
>     > facing drops towards the kni.
>     > the way I see it the only difference now is that I have another
>     threads
>     > which handles an mbuf and frees it once processing is completed.
>     > Can anyone assist with this case please?
>     >
>     > Thanks!
>     >
> 
>