Re: [dpdk-dev] Jumbo Frame in pktgen & dpdk-pktgen

[Nirmal Sarkar <nirmal.kisan@gmail.com>]

Hello,

Thanks for your reply.

Using *testpmd* [*--mbuf-size=2048 --max-pkt-len=9600*], I can send/receive
Jumbo pkt over vmxnet3 without any change in the dpdk source code.
Ref: https://doc.dpdk.org/dts/test_plans/jumboframes_test_plan.html

Can you please tell me why I will not be able to send jumbo packet from
pktgen without doing any change in dpdk/EAL ?

Regards,
N. Sarkar

On Wed, Nov 27, 2019 at 8:42 PM Wiles, Keith <keith.wiles@intel.com> wrote:

>
>
> > On Nov 26, 2019, at 2:21 AM, Nirmal Sarkar <nirmal.kisan@gmail.com>
> wrote:
> >
> > Hello,
> >
> > To support Jumbo frame in dpdk-pktgen,  changes were suggested in dpdk
> libraries also apart from pktgen code.
> > lib/librte_mbuf/rte_mbuf.h
> > lib/common/pg_inet.h
> >
> > But dpdk framework already supports jumbo frame [using --enable-jumbo &
> --max-pkt-len flag].
> > Can you please help me to understand why do we need to change the
> libraries in dpdk ?
>
> These flags are for l3fwd type example apps and not a flag in the EAL or
> core code.
>
> It appears the the port configs needs to be changed to enable jumbo
> frames. The patch below seemed to work for Lee and I have not tried the
> patch changes.
> >
> > Regards,
> > N. Sarkar
> >
> > On Thu, Nov 21, 2019 at 12:24 AM Wiles, Keith <keith.wiles@intel.com>
> wrote:
> >
> >
> > > On Nov 20, 2019, at 6:09 AM, Nirmal Sarkar <nirmal.kisan@gmail.com>
> wrote:
> > >
> > > Hello,
> > >
> > > Thanks for the help.
> > > As I'm using DPDK-18.11.1, I did not find the definition of
> > > "RTE_ETHER_MAX_LEN" in lib/librte_net/rte_ether.h file.
> > > So I set "ETHER_MAX_LEN" value to 9600.
> > > Apart from that I took rest of the changes and with these I'm able to
> send
> > > jumbo frame.
> > > Took tcpdump on the receiving end.
> > >
> > > Suddenly I got stuck at ARP. I could not send packets anymore.
> >
> > Sorry, I can not tell what the error condition is you are hitting, as
> the two screen dumps do not provide me where I should start looking. If you
> can help me understand the issue better.
> > >
> > > I've attached success & failure scenario.
> > >
> > > Regards,
> > > N. Sarkar
> > >
> > > On Wed, Nov 20, 2019 at 2:14 AM Morten Brørup <
> mb@smartsharesystems.com>
> > > wrote:
> > >
> > >> John, Marko,
> > >>
> > >> It seems we are missing documentation about enabling Jumbo frames in
> an
> > >> application, and possibly an example of using the
> rte_eth_dev_info->max_mtu.
> > >>
> > >>
> > >> Med venlig hilsen / kind regards
> > >> - Morten Brørup
> > >>
> > >>> -----Original Message-----
> > >>> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Roberts, Lee A.
> > >>> Sent: Tuesday, November 19, 2019 6:42 PM
> > >>> To: Nirmal Sarkar; dev@dpdk.org
> > >>> Subject: Re: [dpdk-dev] Jumbo Frame in pktgen & dpdk-pktgen
> > >>>
> > >>> Nirmal,
> > >>>
> > >>> Here are the changes that I've been using to allow jumbo frames with
> > >> dpdk-
> > >>> 19.08 and
> > >>> pktgen-19.10.0:
> > >>>
> > >>> diff -r default/dpdk-19.08/lib/librte_mbuf/rte_mbuf.h jumbo/dpdk-
> > >>> 19.08/lib/librte_mbuf/rte_mbuf.h
> > >>> 462c462
> > >>> < #define     RTE_MBUF_DEFAULT_DATAROOM       2048
> > >>> ---
> > >>>> #define     RTE_MBUF_DEFAULT_DATAROOM       9600
> > >>> diff -r default/dpdk-19.08/lib/librte_net/rte_ether.h jumbo/dpdk-
> > >>> 19.08/lib/librte_net/rte_ether.h
> > >>> 33c33
> > >>> < #define RTE_ETHER_MAX_LEN   1518  /**< Maximum frame len, including
> > >> CRC.
> > >>> */
> > >>> ---
> > >>>> #define RTE_ETHER_MAX_LEN   9600  /**< Maximum frame len, including
> > >> CRC.
> > >>> */
> > >>> diff -r default/pktgen-19.10.0/app/pktgen.c jumbo/pktgen-
> > >>> 19.10.0/app/pktgen.c
> > >>> 749c749
> > >>> <     else if ( (plen >= 1024) && (plen <= PG_ETHER_MAX_LEN))
> > >>> ---
> > >>>>    else if ( (plen >= 1024) && (plen <= 1518))
> > >>> 753c753
> > >>> <     else if (plen > PG_ETHER_MAX_LEN)
> > >>> ---
> > >>>>    else if (plen > 1518)
> > >>> diff -r default/pktgen-19.10.0/lib/common/pg_inet.h jumbo/pktgen-
> > >>> 19.10.0/lib/common/pg_inet.h
> > >>> 379,380c379,380
> > >>> < #define ETH_MTU                     1500    /* Max MTU for
> Ethernet */
> > >>> < #define ETH_MAX_PKT                 1518    /* Max Ethernet frame
> size
> > >> */
> > >>> ---
> > >>>> #define ETH_MTU                     9600    /* Max MTU for Ethernet
> */
> > >>>> #define ETH_MAX_PKT                 9600    /* Max Ethernet frame
> size
> > >> */
> > >>>
> > >>>                                   - Lee Roberts
> > >>>
> > >>>
> > >>> -----Original Message-----
> > >>> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Nirmal Sarkar
> > >>> Sent: Monday, November 18, 2019 10:26 AM
> > >>> To: dev@dpdk.org
> > >>> Subject: [dpdk-dev] Jumbo Frame in pktgen & dpdk-pktgen
> > >>>
> > >>> Hello,
> > >>>
> > >>> I'm trying to explore pktgen and dpdk-pktgen with Jumbo frame.
> > >>>
> > >>> I'm using ubuntu-18.04 system where pktgen is a kernel module and I
> don't
> > >>> have any provision to set it for Jumbo frame.
> > >>> Can you please suggest how to configure Jumbo frame in pktgen ?
> > >>>
> > >>> In dpdk source code, I've modified RTE_MBUF_DEFAULT_DATAROOM [
> > >>> *lib/librte_mbuf/rte_mbuf.h*] value with 9K and built.
> > >>> During testing, I could not send packet size more than 1500 byte.
> > >>> What is the suggestion to overcome this problem ?
> > >>>
> > >>> Regards,
> > >>> N. Sarkar
> > >>
> > > <success.txt><failure.txt>
> >
> > Regards,
> > Keith
> >
>
> Regards,
> Keith
>
>