[dpdk-users] Does vmxnet3 PMD supports LSC=1 ?

[madhukar mythri]

Hi,

Does vmxnet3 PMD support LSC=1(i.e with interrupt mode) for link changes ?

When i enable LSC=1 the functionality works fine, but, when pumping traffic
i'm seeing increasing in CPU load on some cores which is running
"eal-intr-thread" epoll_wait() function for more CPU-time.

Actually, interrupt should come only when Link changes, but, we are seeing
interrupt for each incoming Rx-packet and also a lot of spurious interrupts.
=============
~ # cat /proc/interrupts |grep igb
 58:    1254293          0          0          0   PCI-MSI 1572864-edge
 igb_uio
 59:    1278105          0          0          0   PCI-MSI 5767168-edge
 igb_uio
~ # cat /proc/irq/58/spurious
count 98035
unhandled 0
last_unhandled 0 ms
~ #
==============

Does anyone tried LSC=1 in vmxnet3 PMD based apps and faced similar issues
? If so, please let me know.

Tried with DPDK-18.11, DPDK-19.11 and DPDK-20.05.

Thanks,
Madhukar.