Re: Performance "problem" or how to get power of the DPDK

[Dmitry Kozlyuk <dmitry.kozliuk@gmail.com>]

2022-12-26 22:24 (UTC+0300), Ruslan R. Laishev:
> Sorry, right interface:
>  
> Network devices using DPDK-compatible driver
> ============================================
> 0000:09:00.0 'Ethernet Connection X553 10 GbE SFP+ 15c4' drv=igb_uio unused=ixgbe,vfio-pci
>  
>  
> 26.12.2022, 22:21, "Ruslan R. Laishev" <zator@yandex.ru>:
> There is what i do at xmiter side, may be u will get a quantum to see a code of pupil:  https://pastebin.com/1WMyXtr5

I see nothing terribly wrong there.
If you run it on more then one core each using a distinct Tx queue,
do you see a performance increase?

You might want to remove the shared atomic counter;
use simple per-lcore counters and sum them for display.
Also, if "g_nqueue" is not const, "%" should not be used on the data path.

> > I spent some time with the testpmd, sorry but there is not an ability to get rate information on sending, may be i'll add it into the code ...

Run testpmd as follows to make it transmit packets
(add DPDK options before "--" as needed):

dpdk-testpmd -- --forward-mode=txonly --tx-first

It will print statistics on exit ("exit" or Ctrl+C).

> > Some statistics (rte_eth_stats)  :
> >  
> > Date;Time;Device;Port;Name;Area;In pkts;Out pkts;In bytes;Out bytes;In missed;In errors;Out errors;No mbufs;
> > (payload is 0 octets)
> > 26-12-2022; 22:14:10; 0000:09:00.0; _PEA00:; WAN0; WAN; 0; 21122753; 0; 1563085750; 0; 0; 0; 0
> > 26-12-2022; 22:14:20; 0000:09:00.0; _PEA00:; WAN0; WAN; 0; 21122392; 0; 1563057008; 0; 0; 0; 0
> > 26-12-2022; 22:14:30; 0000:09:00.0; _PEA00:; WAN0; WAN; 0; 21121978; 0; 1563024500; 0; 0; 0; 0
> > 26-12-2022; 22:14:40; 0000:09:00.0; _PEA00:; WAN0; WAN; 0; 21122012; 0; 1563028888; 0; 0; 0; 0
> >  
> > (payload is 1024 octets)
> > 26-12-2022; 22:15:20; 0000:09:00.0; _PEA00:; WAN0; WAN; 0; 5246799; 0; 4648659464; 0; 0; 0; 0
> > 26-12-2022; 22:15:30; 0000:09:00.0; _PEA00:; WAN0; WAN; 0; 5246456; 0; 4648360016; 0; 0; 0; 0
> > 26-12-2022; 22:15:40; 0000:09:00.0; _PEA00:; WAN0; WAN; 0; 5246168; 0; 4648108408; 0; 0; 0; 0
> > 26-12-2022; 22:15:50; 0000:09:00.0; _PEA00:; WAN0; WAN; 0; 5246143; 0; 4648084478; 0; 0; 0; 0
> > 26-12-2022; 22:16:00; 0000:09:00.0; _PEA00:; WAN0; WAN; 0; 5246129; 0; 4648070294; 0; 0; 0; 0
> >  
> > A piece of the DPDK-DEVBIND.SH
> > 0000:02:00.0 'I211 Gigabit Network Connection 1539' if=enp2s0 drv=igb unused=igb_uio,vfio-pci *Active*
> >  
> > 26.12.2022, 16:22, "Ruslan R. Laishev" <zator@yandex.ru>:
> > Thanks for the answer.
> >>  
> >> Oops, sorry, some details:
> >> - one core run generator routine
> >> - one core run routine to save/display statistic
> >>  
> >> core run a generator routine like:
> >>  
> >> while (1) {
> >> get buffer from pool
> >> make eth+ip+udp header (it's static content)
> >> generate payload like memset(packet.payload , 'A' + something, payload_size);
> >> generate packet sequence and CRC32C  - and add it to the payload part
> >> "send" packet to tx_buffer
> >>  
> >> if (tx_buffer.size == tx_buffer.length)
> >> do flush()
> >> }
> >>  
> >> "header; part of the packet : sizeof(eth+ip+udp) -
> >> "payload" part - 20-1024 octets

From your statistics I calculate 74 bytes per packet (Ethernet),
i.e. the theoretical maximum for 10 Gbps is 12.25 Mpps,
with packet budget of 81 ns per packet.

https://calc.pktgen.com/#gbe=20&payload=40&rate=12250000&header=20

> >> RSS - it's on received side, yes ?

Correct.
I asked because it was unclear from the initial message
whether you app does the receiving or not.

P.S. Please avoid top-posting, i.e. reply below the quote.