Hi Stephen,
Have tx queue len was 1024, increasing it to 2048 hasn't changed the
behaviour. IXIA is the receiver in this case, which is definitely(and
tested) capable of receiving more rate than this.

IXIA-TX --->RX(ixgbe-port0)HOST(ixgbe-port1)TX ---> IXIA-RX
Captured the rx packets count at ixgbe-port0 and tx packets count at
ixgbe-port1. These 2 counters are equal and are also equal to the frames
transmitted by IXIA.
But the IXIA-RX packets count reports a few hundreds-to-few thousands of
packets lost on every run.

Thanks & Regards,
Rajasekhar



On Fri, Feb 17, 2023 at 9:56 PM Stephen Hemminger <
stephen@networkplumber.org> wrote:

> On Fri, 17 Feb 2023 11:30:14 +0530
> Rajasekhar Pulluru <pullururajasekhar@gmail.com> wrote:
>
> > Ok Stephen, thanks for the information, I can try that.
> >
> > One of the problems I see with single Tx Queue mode is that Ixia reports
> > packet drops, though I confirmed with the help of counters (before
> invoking
> > tx burst) that all packets are being sent-out. Dumping HW counters don't
> > report any drops in TX.
> > Is there a mechanism in DPDK to debug this?
> >
> > Thanks & Regards,
> > Rajasekhar
>
> The common usage in DPDK is to have one transmit queue per DPDK thread
> doing
> transmits.  If the transmit queue is not configured with enough depth.
>
> The most common packet flow in DPDK is packets getting received, modified
> then transmitted. With that pattern, packet loss is at the receiver when
> the CPU can't keep up with the packet rate arriving.
>