1.. zephyr:code-sample:: zbus-benchmark
2   :name: Benchmarking
3   :relevant-api: zbus_apis
4
5   Measure the time for sending 256KB from a producer to N consumers.
6
7This sample implements an application to measure the time for sending 256KB from the producer to the
8consumers.
9
10Building and Running
11********************
12
13.. zephyr-app-commands::
14   :zephyr-app: samples/subsys/zbus/dyn_channel
15   :host-os: unix
16   :board: qemu_cortex_m3
17   :gen-args: -DCONFIG_BM_MESSAGE_SIZE=512 -DCONFIG_BM_ONE_TO=1 -DCONFIG_BM_LISTENERS=y
18   :goals: build run
19
20Notice we have the following parameters:
21
22* **CONFIG_BM_MESSAGE_SIZE** the size of the message to be transferred (2 to 4096 bytes);
23* **CONFIG_BM_ONE_TO** number of consumers to send (1 up to 8 consumers);
24* **CONFIG_BM_LISTENERS** Use y to perform the benchmark listeners;
25* **CONFIG_BM_SUBSCRIBERS** Use y to perform the benchmark subscribers;
26* **CONFIG_BM_MSG_SUBSCRIBERS** Use y to perform the benchmark message subscribers.
27
28Sample Output
29=============
30The result would be something like:
31
32.. code-block:: console
33
34   *** Booting Zephyr OS build zephyr-vX.Y.Z ***
35   I: Benchmark 1 to 1 using LISTENERS to transmit with message size: 512 bytes
36   I: Bytes sent = 262144, received = 262144
37   I: Average data rate: 12.62MB/s
38   I: Duration: 0.019805908s
39
40   @19805
41
42
43Running the benchmark automatically
44===================================
45
46There is a `Robot framework <https://robotframework.org/>`_ script called ``benchmark_256KB.robot`` which runs all the input combinations as the complete benchmark.
47The resulting file, ``zbus_dyn_benchmark_256KB.csv`` is generated in the project root folder. It takes a long time to execute. In the CSV file, we have the following columns:
48
49+-----------------+---------------------+--------------------------+---------------+-------------+-------------+
50| Observer type   | Number of consumers | Message size (bytes)     | Duration (ns) | RAM (bytes) | ROM (bytes) |
51+=================+=====================+==========================+===============+=============+=============+
52| LIS/SUB/MSG_SUB | 1,4,8               | 2,8,32,128,512           | float         | int         | int         |
53+-----------------+---------------------+--------------------------+---------------+-------------+-------------+
54
55The complete benchmark command using Robot framework is:
56
57.. code-block:: console
58
59    robot --variable serial_port:/dev/ttyACM0 --variable board:nrf52dk/nrf52832 -d /tmp/benchmark_out   benchmark_256KB.robot
60
61An example of execution using the ``nrf52dk/nrf52832`` board would generate a file like this:
62
63.. code-block::
64
65   LISTENERS,1,2,890787.3333333334,9247,23091
66   LISTENERS,1,8,237925.0,9253,23091
67   LISTENERS,1,32,74513.0,9277,23151
68   LISTENERS,1,128,33813.0,9565,23231
69   LISTENERS,1,512,35746.0,10717,23623
70   LISTENERS,4,2,314198.3333333333,9274,23142
71   LISTENERS,4,8,82244.33333333333,9280,23142
72   LISTENERS,4,32,24057.333333333332,9304,23202
73   LISTENERS,4,128,9816.0,9592,23282
74   LISTENERS,4,512,9277.0,10744,23674
75   LISTENERS,8,2,211465.66666666666,9310,23202
76   LISTENERS,8,8,56294.0,9316,23210
77   LISTENERS,8,32,15635.0,9340,23270
78   LISTENERS,8,128,5818.0,9628,23350
79   LISTENERS,8,512,4862.0,10780,23742
80   SUBSCRIBERS,1,2,7804351.333333333,9927,23463
81   SUBSCRIBERS,1,8,1978179.3333333333,9933,23463
82   SUBSCRIBERS,1,32,514139.3333333333,9957,23523
83   SUBSCRIBERS,1,128,146759.0,10309,23603
84   SUBSCRIBERS,1,512,55104.0,11845,23995
85   SUBSCRIBERS,4,2,5551961.0,11994,24134
86   SUBSCRIBERS,4,8,1395009.0,12000,24134
87   SUBSCRIBERS,4,32,354583.3333333333,12024,24194
88   SUBSCRIBERS,4,128,92976.66666666667,12568,24274
89   SUBSCRIBERS,4,512,28015.0,15256,24666
90   SUBSCRIBERS,8,2,5449839.0,14750,24858
91   SUBSCRIBERS,8,8,1321766.6666666667,14756,24866
92   SUBSCRIBERS,8,32,332804.0,14780,24926
93   SUBSCRIBERS,8,128,85489.33333333333,15580,25006
94   SUBSCRIBERS,8,512,23905.0,19804,25398
95   MSG_SUBSCRIBERS,1,2,8783538.333333334,10371,25615
96   MSG_SUBSCRIBERS,1,8,2249592.6666666665,10377,25615
97   MSG_SUBSCRIBERS,1,32,610168.0,10401,25675
98   MSG_SUBSCRIBERS,1,128,207295.0,10753,25755
99   MSG_SUBSCRIBERS,1,512,143584.66666666666,12289,26147
100   MSG_SUBSCRIBERS,4,2,5787699.0,12318,26126
101   MSG_SUBSCRIBERS,4,8,1473907.0,12324,26126
102   MSG_SUBSCRIBERS,4,32,396127.6666666667,12348,26186
103   MSG_SUBSCRIBERS,4,128,126362.66666666667,12892,26266
104   MSG_SUBSCRIBERS,4,512,59040.666666666664,15580,26658
105   MSG_SUBSCRIBERS,8,2,5453999.333333333,14914,26610
106   MSG_SUBSCRIBERS,8,8,1356312.3333333333,14920,26650
107   MSG_SUBSCRIBERS,8,32,361368.3333333333,14944,26710
108   MSG_SUBSCRIBERS,8,128,113148.66666666667,15744,26790
109   MSG_SUBSCRIBERS,8,512,51218.333333333336,19968,27182
110