Re: [RFC PATCH v2 08/10] net: sched: pfifo_fast use alf_queue

On Fri, Jul 15, 2016 at 03:18:12PM -0700, John Fastabend wrote:

nolock (pfifo_fast)
1:  1440293 1421602 1409553 1393469 1424543
2:  1754890 1819292 1727948 1797711 1743427
4:  3282665 3344095 3315220 3332777 3348972
8:  2940079 1644450 2950777 2922085 2946310
12: 2042084 2610060 2857581 3493162 3104611

lock (pfifo_fast)
1:  1471479 1469142 1458825 1456788 1453952
2:  1746231 1749490 1753176 1753780 1755959
4:  1119626 1120515 1121478 1119220 1121115
8:  1001471  999308 1000318 1000776 1000384
12:  989269  992122  991590  986581  990430

So then if we just use the first test example because I'm being a
bit lazy and don't want to calculate the avg/mean/whatever we get
a pfifo_fast chart like,

      locked             nolock           diff
---------------------------------------------------
1     1471479            1440293          −  31186
2     1746231            1754890          +   8659
4     1119626            3282665          +2163039
8     1119626            2940079          +1820453
12     989269            2857581*         +1868312

...

Also I'm going to take a look at Jesper's microbenchmark numbers but I
think if I can convince myself that using skb_array helps or at least
does no harm I might push to have this include with skb_array and then
work on optimizing the ring type/kind/etc. as a follow up patch.
Additionally it does seem to provide goodness on the pfifo_fast single
queue case.

Agree. I think the pfifo_fast gains worth applying this patch set
as-is and work on further improvements in follow up.