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* [dpdk-dev] [RFC 0/6] New sync modes for ring
@ 2020-02-24 11:35 Konstantin Ananyev
  2020-02-24 11:35 ` [dpdk-dev] [RFC 1/6] test/ring: add contention stress test Konstantin Ananyev
                   ` (8 more replies)
  0 siblings, 9 replies; 146+ messages in thread
From: Konstantin Ananyev @ 2020-02-24 11:35 UTC (permalink / raw)
  To: dev; +Cc: olivier.matz, Konstantin Ananyev

Upfront note - that RFC is not a complete patch.
It introduces an ABI breakage, plus it doesn't update ring_elem
code properly, etc.
I plan to deal with all these things in later versions.
Right now I seek an initial feedback about proposed ideas.
Would also ask people to repeat performance tests (see below)
on their platforms to confirm the impact.

More and more customers use(/try to use) DPDK based apps within
overcommitted systems (multiple acttive threads over same pysical cores):
VM, container deployments, etc.
One quite common problem they hit: Lock-Holder-Preemption with rte_ring.
LHP is quite a common problem for spin-based sync primitives
(spin-locks, etc.) on overcommitted systems.
The situation gets much worse when some sort of
fair-locking technique is used (ticket-lock, etc.).
As now not only lock-owner but also lock-waiters scheduling
order matters a lot.
This is a well-known problem for kernel within VMs:
http://www-archive.xenproject.org/files/xensummitboston08/LHP.pdf
https://www.cs.hs-rm.de/~kaiser/events/wamos2017/Slides/selcuk.pdf
The problem with rte_ring is that while head accusion is sort of
un-fair locking, waiting on tail is very similar to ticket lock schema -
tail has to be updated in particular order.
That makes current rte_ring implementation to perform
really pure on some overcommited scenarios.
While it is probably not possible to completely resolve this problem in
userspace only (without some kernel communication/intervention),
removing fairness in tail update can mitigate it significantly.
So this RFC proposes two new optional ring synchronization modes:
1) Head/Tail Sync (HTS) mode
In that mode enqueue/dequeue operation is fully serialized:
    only one thread at a time is allowed to perform given op.
    As another enhancement provide ability to split enqueue/dequeue
    operation into two phases:
      - enqueue/dequeue start
      - enqueue/dequeue finish
    That allows user to inspect objects in the ring without removing
    them from it (aka MT safe peek).
2) Relaxed Tail Sync (RTS)
The main difference from original MP/MC algorithm is that
tail value is increased not by every thread that finished enqueue/dequeue,
but only by the last one.
That allows threads to avoid spinning on ring tail value,
leaving actual tail value change to the last thread in the update queue.

Test results on IA (see below) show significant improvements
for average enqueue/dequeue op times on overcommitted systems.
For 'classic' DPDK deployments (one thread per core) original MP/MC
algorithm still shows best numbers, though for 64-bit target
RTS numbers are not that far away.
Numbers were produced by ring_stress_*autotest
(first patch in these series).

X86_64 @ Intel(R) Xeon(R) Platinum 8160 CPU @ 2.10GHz
DEQ+ENQ average cycles/obj

                                                MP/MC      HTS     RTS
1thread@1core(--lcores=6-7)                     8.00       8.15    8.99
2thread@2core(--lcores=6-8)                     19.14      19.61   20.35
4thread@4core(--lcores=6-10)                    29.43      29.79   31.82
8thread@8core(--lcores=6-14)                    110.59     192.81  119.50
16thread@16core(--lcores=6-22)                  461.03     813.12  495.59
32thread/@32core(--lcores='6-22,55-70')         982.90     1972.38 1160.51

2thread@1core(--lcores='6,(10-11)@7'            20140.50   23.58   25.14
4thread@2core(--lcores='6,(10-11)@7,(20-21)@8'  153680.60  76.88   80.05
8thread@2core(--lcores='6,(10-13)@7,(20-23)@8'  280314.32  294.72  318.79
16thread@2core(--lcores='6,(10-17)@7,(20-27)@8' 643176.59  1144.02 1175.14
32thread@2core(--lcores='6,(10-25)@7,(30-45)@8' 4264238.80 4627.48 4892.68

8thread@2core(--lcores='6,(10-17)@(7,8))'       321085.98  298.59  307.47
16thread@4core(--lcores='6,(20-35)@(7-10))'     1900705.61 575.35  678.29
32thread@4core(--lcores='6,(20-51)@(7-10))'     5510445.85 2164.36 2714.12

i686 @ Intel(R) Xeon(R) Platinum 8160 CPU @ 2.10GHz
DEQ+ENQ average cycles/obj

                                                MP/MC      HTS     RTS
1thread@1core(--lcores=6-7)                     7.85       12.13   11.31
2thread@2core(--lcores=6-8)                     17.89      24.52   21.86
8thread@8core(--lcores=6-14)                    32.58      354.20  54.58
32thread/@32core(--lcores='6-22,55-70')         813.77     6072.41 2169.91

2thread@1core(--lcores='6,(10-11)@7'            16095.00   36.06   34.74
8thread@2core(--lcores='6,(10-13)@7,(20-23)@8'  1140354.54 346.61  361.57
16thread@2core(--lcores='6,(10-17)@7,(20-27)@8' 1920417.86 1314.90 1416.65

8thread@2core(--lcores='6,(10-17)@(7,8))'       594358.61  332.70  357.74
32thread@4core(--lcores='6,(20-51)@(7-10))'     5319896.86 2836.44 3028.87

Konstantin Ananyev (6):
  test/ring: add contention stress test
  ring: rework ring layout to allow new sync schemes
  ring: introduce RTS ring mode
  test/ring: add contention stress test for RTS ring
  ring: introduce HTS ring mode
  test/ring: add contention stress test for HTS ring

 app/test/Makefile                      |   3 +
 app/test/meson.build                   |   3 +
 app/test/test_pdump.c                  |   6 +-
 app/test/test_ring_hts_stress.c        |  28 ++
 app/test/test_ring_rts_stress.c        |  28 ++
 app/test/test_ring_stress.c            |  27 ++
 app/test/test_ring_stress.h            | 477 +++++++++++++++++++
 lib/librte_pdump/rte_pdump.c           |   2 +-
 lib/librte_port/rte_port_ring.c        |  12 +-
 lib/librte_ring/Makefile               |   4 +-
 lib/librte_ring/meson.build            |   4 +-
 lib/librte_ring/rte_ring.c             |  84 +++-
 lib/librte_ring/rte_ring.h             | 619 +++++++++++++++++++++++--
 lib/librte_ring/rte_ring_elem.h        |   8 +-
 lib/librte_ring/rte_ring_hts_generic.h | 228 +++++++++
 lib/librte_ring/rte_ring_rts_generic.h | 240 ++++++++++
 16 files changed, 1721 insertions(+), 52 deletions(-)
 create mode 100644 app/test/test_ring_hts_stress.c
 create mode 100644 app/test/test_ring_rts_stress.c
 create mode 100644 app/test/test_ring_stress.c
 create mode 100644 app/test/test_ring_stress.h
 create mode 100644 lib/librte_ring/rte_ring_hts_generic.h
 create mode 100644 lib/librte_ring/rte_ring_rts_generic.h

-- 
2.17.1


^ permalink raw reply	[flat|nested] 146+ messages in thread

end of thread, other threads:[~2020-04-21 11:31 UTC | newest]

Thread overview: 146+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-02-24 11:35 [dpdk-dev] [RFC 0/6] New sync modes for ring Konstantin Ananyev
2020-02-24 11:35 ` [dpdk-dev] [RFC 1/6] test/ring: add contention stress test Konstantin Ananyev
2020-02-24 11:35 ` [dpdk-dev] [RFC 2/6] ring: rework ring layout to allow new sync schemes Konstantin Ananyev
2020-02-24 11:35 ` [dpdk-dev] [RFC 3/6] ring: introduce RTS ring mode Konstantin Ananyev
2020-02-24 11:35 ` [dpdk-dev] [RFC 4/6] test/ring: add contention stress test for RTS ring Konstantin Ananyev
2020-02-24 11:35 ` [dpdk-dev] [RFC 5/6] ring: introduce HTS ring mode Konstantin Ananyev
2020-03-25 20:44   ` Honnappa Nagarahalli
2020-03-26 12:26     ` Ananyev, Konstantin
2020-02-24 11:35 ` [dpdk-dev] [RFC 6/6] test/ring: add contention stress test for HTS ring Konstantin Ananyev
2020-02-24 16:59 ` [dpdk-dev] [RFC 0/6] New sync modes for ring Stephen Hemminger
2020-02-24 17:59   ` Jerin Jacob
2020-02-24 19:35     ` Stephen Hemminger
2020-02-24 20:52       ` Honnappa Nagarahalli
2020-02-25 11:45         ` Ananyev, Konstantin
2020-02-25 13:41       ` Ananyev, Konstantin
2020-02-26 16:53         ` Morten Brørup
2020-02-27 10:31         ` Jerin Jacob
2020-02-28  0:17           ` David Christensen
2020-03-20 16:45             ` Ananyev, Konstantin
2020-02-25  0:58     ` Honnappa Nagarahalli
2020-02-25 15:14       ` Ananyev, Konstantin
2020-03-25 20:43 ` Honnappa Nagarahalli
2020-03-26  1:50   ` Ananyev, Konstantin
2020-03-30 21:29     ` Honnappa Nagarahalli
2020-03-30 23:37       ` Honnappa Nagarahalli
2020-03-31 17:21         ` Ananyev, Konstantin
2020-03-31 16:43 ` [dpdk-dev] [PATCH v1 0/8] " Konstantin Ananyev
2020-03-31 16:43   ` [dpdk-dev] [PATCH v1 1/8] test/ring: add contention stress test Konstantin Ananyev
2020-03-31 16:43   ` [dpdk-dev] [PATCH v1 2/8] ring: prepare ring to allow new sync schemes Konstantin Ananyev
2020-03-31 16:43   ` [dpdk-dev] [PATCH v1 3/8] ring: introduce RTS ring mode Konstantin Ananyev
2020-03-31 16:43   ` [dpdk-dev] [PATCH v1 4/8] test/ring: add contention stress test for RTS ring Konstantin Ananyev
2020-03-31 16:43   ` [dpdk-dev] [PATCH v1 5/8] ring: introduce HTS ring mode Konstantin Ananyev
2020-03-31 16:43   ` [dpdk-dev] [PATCH v1 6/8] test/ring: add contention stress test for HTS ring Konstantin Ananyev
2020-03-31 16:43   ` [dpdk-dev] [PATCH v1 7/8] ring: introduce peek style API Konstantin Ananyev
2020-03-31 16:43   ` [dpdk-dev] [PATCH v1 8/8] test/ring: add stress test for MT peek API Konstantin Ananyev
2020-04-02 22:09   ` [dpdk-dev] [PATCH v2 0/9] New sync modes for ring Konstantin Ananyev
2020-04-02 22:09     ` [dpdk-dev] [PATCH v2 1/9] test/ring: add contention stress test Konstantin Ananyev
2020-04-02 22:09     ` [dpdk-dev] [PATCH v2 2/9] ring: prepare ring to allow new sync schemes Konstantin Ananyev
2020-04-02 22:09     ` [dpdk-dev] [PATCH v2 3/9] ring: introduce RTS ring mode Konstantin Ananyev
2020-04-02 22:09     ` [dpdk-dev] [PATCH v2 4/9] test/ring: add contention stress test for RTS ring Konstantin Ananyev
2020-04-02 22:09     ` [dpdk-dev] [PATCH v2 5/9] ring: introduce HTS ring mode Konstantin Ananyev
2020-04-02 22:09     ` [dpdk-dev] [PATCH v2 6/9] test/ring: add contention stress test for HTS ring Konstantin Ananyev
2020-04-02 22:09     ` [dpdk-dev] [PATCH v2 7/9] ring: introduce peek style API Konstantin Ananyev
2020-04-02 22:09     ` [dpdk-dev] [PATCH v2 8/9] test/ring: add stress test for MT peek API Konstantin Ananyev
2020-04-02 22:09     ` [dpdk-dev] [PATCH v2 9/9] ring: add C11 memory model for new sync modes Konstantin Ananyev
2020-04-03 17:42     ` [dpdk-dev] [PATCH v3 0/9] New sync modes for ring Konstantin Ananyev
2020-04-03 17:42       ` [dpdk-dev] [PATCH v3 1/9] test/ring: add contention stress test Konstantin Ananyev
2020-04-08  4:59         ` Honnappa Nagarahalli
2020-04-09 12:36           ` Ananyev, Konstantin
2020-04-09 13:00             ` Ananyev, Konstantin
2020-04-10 18:01               ` Honnappa Nagarahalli
2020-04-10 16:59             ` Honnappa Nagarahalli
2020-04-03 17:42       ` [dpdk-dev] [PATCH v3 2/9] ring: prepare ring to allow new sync schemes Konstantin Ananyev
2020-04-08  4:59         ` Honnappa Nagarahalli
2020-04-09 13:39           ` Ananyev, Konstantin
2020-04-10 20:15             ` Honnappa Nagarahalli
2020-04-03 17:42       ` [dpdk-dev] [PATCH v3 3/9] ring: introduce RTS ring mode Konstantin Ananyev
2020-04-04 17:27         ` Wang, Haiyue
2020-04-08  5:00         ` Honnappa Nagarahalli
2020-04-09 14:52           ` Ananyev, Konstantin
2020-04-10 23:10             ` Honnappa Nagarahalli
2020-04-13 14:29               ` David Marchand
2020-04-13 16:42                 ` Honnappa Nagarahalli
2020-04-14 13:47                   ` David Marchand
2020-04-14 15:57                     ` Honnappa Nagarahalli
2020-04-14 16:21                       ` Ananyev, Konstantin
2020-04-14 13:18               ` Ananyev, Konstantin
2020-04-14 15:58                 ` Honnappa Nagarahalli
2020-04-03 17:42       ` [dpdk-dev] [PATCH v3 4/9] test/ring: add contention stress test for RTS ring Konstantin Ananyev
2020-04-03 17:42       ` [dpdk-dev] [PATCH v3 5/9] ring: introduce HTS ring mode Konstantin Ananyev
2020-04-13 23:27         ` Honnappa Nagarahalli
2020-04-14 16:12           ` Ananyev, Konstantin
2020-04-14 17:06             ` Honnappa Nagarahalli
2020-04-03 17:42       ` [dpdk-dev] [PATCH v3 6/9] test/ring: add contention stress test for HTS ring Konstantin Ananyev
2020-04-03 17:42       ` [dpdk-dev] [PATCH v3 7/9] ring: introduce peek style API Konstantin Ananyev
2020-04-14  3:45         ` Honnappa Nagarahalli
2020-04-14 16:47           ` Ananyev, Konstantin
2020-04-14 17:30             ` Honnappa Nagarahalli
2020-04-14 22:24               ` Ananyev, Konstantin
2020-04-03 17:42       ` [dpdk-dev] [PATCH v3 8/9] test/ring: add stress test for MT peek API Konstantin Ananyev
2020-04-03 17:42       ` [dpdk-dev] [PATCH v3 9/9] ring: add C11 memory model for new sync modes Konstantin Ananyev
2020-04-04 14:16         ` [dpdk-dev] 回复:[PATCH " 周介龙
2020-04-14  4:28         ` [dpdk-dev] [PATCH " Honnappa Nagarahalli
2020-04-14 18:29           ` Ananyev, Konstantin
2020-04-15 20:28           ` Ananyev, Konstantin
2020-04-17 13:36       ` [dpdk-dev] [PATCH v4 0/9] New sync modes for ring Konstantin Ananyev
2020-04-17 13:36         ` [dpdk-dev] [PATCH v4 1/9] test/ring: add contention stress test Konstantin Ananyev
2020-04-17 13:36         ` [dpdk-dev] [PATCH v4 2/9] ring: prepare ring to allow new sync schemes Konstantin Ananyev
2020-04-17 13:36         ` [dpdk-dev] [PATCH v4 3/9] ring: introduce RTS ring mode Konstantin Ananyev
2020-04-17 13:36         ` [dpdk-dev] [PATCH v4 4/9] test/ring: add contention stress test for RTS ring Konstantin Ananyev
2020-04-17 13:36         ` [dpdk-dev] [PATCH v4 5/9] ring: introduce HTS ring mode Konstantin Ananyev
2020-04-17 13:36         ` [dpdk-dev] [PATCH v4 6/9] test/ring: add contention stress test for HTS ring Konstantin Ananyev
2020-04-17 13:36         ` [dpdk-dev] [PATCH v4 7/9] ring: introduce peek style API Konstantin Ananyev
2020-04-17 13:36         ` [dpdk-dev] [PATCH v4 8/9] test/ring: add stress test for MT peek API Konstantin Ananyev
2020-04-17 13:36         ` [dpdk-dev] [PATCH v4 9/9] test/ring: add functional tests for new sync modes Konstantin Ananyev
2020-04-18 16:32         ` [dpdk-dev] [PATCH v5 0/9] New sync modes for ring Konstantin Ananyev
2020-04-18 16:32           ` [dpdk-dev] [PATCH v5 1/9] test/ring: add contention stress test Konstantin Ananyev
2020-04-19  2:30             ` Honnappa Nagarahalli
2020-04-19  8:03               ` David Marchand
2020-04-19 11:47                 ` Ananyev, Konstantin
2020-04-18 16:32           ` [dpdk-dev] [PATCH v5 2/9] ring: prepare ring to allow new sync schemes Konstantin Ananyev
2020-04-19  2:31             ` Honnappa Nagarahalli
2020-04-18 16:32           ` [dpdk-dev] [PATCH v5 3/9] ring: introduce RTS ring mode Konstantin Ananyev
2020-04-19  2:31             ` Honnappa Nagarahalli
2020-04-18 16:32           ` [dpdk-dev] [PATCH v5 4/9] test/ring: add contention stress test for RTS ring Konstantin Ananyev
2020-04-19  2:31             ` Honnappa Nagarahalli
2020-04-18 16:32           ` [dpdk-dev] [PATCH v5 5/9] ring: introduce HTS ring mode Konstantin Ananyev
2020-04-19  2:31             ` Honnappa Nagarahalli
2020-04-18 16:32           ` [dpdk-dev] [PATCH v5 6/9] test/ring: add contention stress test for HTS ring Konstantin Ananyev
2020-04-19  2:31             ` Honnappa Nagarahalli
2020-04-18 16:32           ` [dpdk-dev] [PATCH v5 7/9] ring: introduce peek style API Konstantin Ananyev
2020-04-19  2:31             ` Honnappa Nagarahalli
2020-04-19 18:32               ` Ananyev, Konstantin
2020-04-19 19:12                 ` Ananyev, Konstantin
2020-04-19 21:14                   ` Honnappa Nagarahalli
2020-04-19 22:41                     ` Ananyev, Konstantin
2020-04-18 16:32           ` [dpdk-dev] [PATCH v5 8/9] test/ring: add stress test for MT peek API Konstantin Ananyev
2020-04-19  2:32             ` Honnappa Nagarahalli
2020-04-18 16:32           ` [dpdk-dev] [PATCH v5 9/9] test/ring: add functional tests for new sync modes Konstantin Ananyev
2020-04-19  2:32             ` Honnappa Nagarahalli
2020-04-19  2:32           ` [dpdk-dev] [PATCH v5 0/9] New sync modes for ring Honnappa Nagarahalli
2020-04-20 12:11           ` [dpdk-dev] [PATCH v6 00/10] " Konstantin Ananyev
2020-04-20 12:11             ` [dpdk-dev] [PATCH v6 01/10] test/ring: add contention stress test Konstantin Ananyev
2020-04-20 12:11             ` [dpdk-dev] [PATCH v6 02/10] ring: prepare ring to allow new sync schemes Konstantin Ananyev
2020-04-20 12:11             ` [dpdk-dev] [PATCH v6 03/10] ring: introduce RTS ring mode Konstantin Ananyev
2020-04-20 12:11             ` [dpdk-dev] [PATCH v6 04/10] test/ring: add contention stress test for RTS ring Konstantin Ananyev
2020-04-20 12:11             ` [dpdk-dev] [PATCH v6 05/10] ring: introduce HTS ring mode Konstantin Ananyev
2020-04-20 12:11             ` [dpdk-dev] [PATCH v6 06/10] test/ring: add contention stress test for HTS ring Konstantin Ananyev
2020-04-20 12:11             ` [dpdk-dev] [PATCH v6 07/10] ring: introduce peek style API Konstantin Ananyev
2020-04-20 12:11             ` [dpdk-dev] [PATCH v6 08/10] test/ring: add stress test for MT peek API Konstantin Ananyev
2020-04-20 12:11             ` [dpdk-dev] [PATCH v6 09/10] test/ring: add functional tests for new sync modes Konstantin Ananyev
2020-04-20 12:11             ` [dpdk-dev] [PATCH v6 10/10] doc: update ring guide Konstantin Ananyev
2020-04-20 13:47               ` David Marchand
2020-04-20 14:07                 ` Ananyev, Konstantin
2020-04-20 12:28             ` [dpdk-dev] [PATCH v7 00/10] New sync modes for ring Konstantin Ananyev
2020-04-20 12:28               ` [dpdk-dev] [PATCH v7 01/10] test/ring: add contention stress test Konstantin Ananyev
2020-04-20 12:28               ` [dpdk-dev] [PATCH v7 02/10] ring: prepare ring to allow new sync schemes Konstantin Ananyev
2020-04-20 12:28               ` [dpdk-dev] [PATCH v7 03/10] ring: introduce RTS ring mode Konstantin Ananyev
2020-04-20 12:28               ` [dpdk-dev] [PATCH v7 04/10] test/ring: add contention stress test for RTS ring Konstantin Ananyev
2020-04-20 12:28               ` [dpdk-dev] [PATCH v7 05/10] ring: introduce HTS ring mode Konstantin Ananyev
2020-04-20 12:28               ` [dpdk-dev] [PATCH v7 06/10] test/ring: add contention stress test for HTS ring Konstantin Ananyev
2020-04-20 12:28               ` [dpdk-dev] [PATCH v7 07/10] ring: introduce peek style API Konstantin Ananyev
2020-04-20 12:28               ` [dpdk-dev] [PATCH v7 08/10] test/ring: add stress test for MT peek API Konstantin Ananyev
2020-04-20 12:28               ` [dpdk-dev] [PATCH v7 09/10] test/ring: add functional tests for new sync modes Konstantin Ananyev
2020-04-20 12:28               ` [dpdk-dev] [PATCH v7 10/10] doc: update ring guide Konstantin Ananyev
2020-04-21 11:31               ` [dpdk-dev] [PATCH v7 00/10] New sync modes for ring David Marchand

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