linux/samples
Jesper Dangaard Brouer 0fca931a6f samples/bpf: program demonstrating access to xdp_rxq_info
This sample program can be used for monitoring and reporting how many
packets per sec (pps) are received per NIC RX queue index and which
CPU processed the packet. In itself it is a useful tool for quickly
identifying RSS imbalance issues, see below.

The default XDP action is XDP_PASS in-order to provide a monitor
mode. For benchmarking purposes it is possible to specify other XDP
actions on the cmdline --action.

Output below shows an imbalance RSS case where most RXQ's deliver to
CPU-0 while CPU-2 only get packets from a single RXQ.  Looking at
things from a CPU level the two CPUs are processing approx the same
amount, BUT looking at the rx_queue_index levels it is clear that
RXQ-2 receive much better service, than other RXQs which all share CPU-0.

Running XDP on dev:i40e1 (ifindex:3) action:XDP_PASS
XDP stats       CPU     pps         issue-pps
XDP-RX CPU      0       900,473     0
XDP-RX CPU      2       906,921     0
XDP-RX CPU      total   1,807,395

RXQ stats       RXQ:CPU pps         issue-pps
rx_queue_index    0:0   180,098     0
rx_queue_index    0:sum 180,098
rx_queue_index    1:0   180,098     0
rx_queue_index    1:sum 180,098
rx_queue_index    2:2   906,921     0
rx_queue_index    2:sum 906,921
rx_queue_index    3:0   180,098     0
rx_queue_index    3:sum 180,098
rx_queue_index    4:0   180,082     0
rx_queue_index    4:sum 180,082
rx_queue_index    5:0   180,093     0
rx_queue_index    5:sum 180,093

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-05 15:21:22 -08:00
..
auxdisplay License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
blackfin samples: move blackfin gptimers-example from Documentation 2016-10-10 07:12:02 -06:00
bpf samples/bpf: program demonstrating access to xdp_rxq_info 2018-01-05 15:21:22 -08:00
configfs configfs: make config_item_type const 2017-10-19 16:15:15 +02:00
connector A relatively calm cycle for the docs tree again. 2017-11-13 08:25:06 -08:00
hidraw kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
hw_breakpoint
kdb
kfifo kfifo: clean up example to not use page_link 2017-07-12 16:26:01 -07:00
kobject
kprobes Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 13:05:08 -08:00
livepatch livepatch: add (un)patch callbacks 2017-10-19 10:08:56 +02:00
mei License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
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rpmsg
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statx kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
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trace_printk
uhid kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
v4l [media] media: v4l2-pci-skeleton: Fix error handling path in 'skeleton_probe()' 2017-10-04 16:55:02 -03:00
vfio-mdev vfio-mdev/samples: make mdev_fops const and static 2017-10-02 12:40:05 -06:00
watchdog License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Kconfig livepatch: introduce shadow variable API 2017-09-14 23:06:12 +02:00
Makefile statx: Add a system call to make enhanced file info available 2017-03-02 20:51:15 -05:00