xref: /linux/Documentation/tools/rtla/rtla-timerlat-hist.rst (revision 68a052239fc4b351e961f698b824f7654a346091)
1.. |tool| replace:: timerlat hist
2
3=====================
4rtla-timerlat-hist
5=====================
6------------------------------------------------
7Histograms of the operating system timer latency
8------------------------------------------------
9
10:Manual section: 1
11
12SYNOPSIS
13========
14**rtla timerlat hist** [*OPTIONS*] ...
15
16DESCRIPTION
17===========
18
19.. include:: common_timerlat_description.rst
20
21The **rtla timerlat hist** displays a histogram of each tracer event
22occurrence. This tool uses the periodic information, and the
23**osnoise:** tracepoints are enabled when using the **-T** option.
24
25OPTIONS
26=======
27
28.. include:: common_timerlat_options.rst
29
30.. include:: common_hist_options.rst
31
32.. include:: common_options.rst
33
34.. include:: common_timerlat_aa.rst
35
36EXAMPLE
37=======
38In the example below, **rtla timerlat hist** is set to run for *10* minutes,
39in the cpus *0-4*, *skipping zero* only lines. Moreover, **rtla timerlat
40hist** will change the priority of the *timerlat* threads to run under
41*SCHED_DEADLINE* priority, with a *100us* runtime every *1ms* period. The
42*1ms* period is also passed to the *timerlat* tracer. Auto-analysis is disabled
43to reduce overhead ::
44
45  [root@alien ~]# timerlat hist -d 10m -c 0-4 -P d:100us:1ms -p 1000 --no-aa
46  # RTLA timerlat histogram
47  # Time unit is microseconds (us)
48  # Duration:   0 00:10:00
49  Index   IRQ-000   Thr-000   IRQ-001   Thr-001   IRQ-002   Thr-002   IRQ-003   Thr-003   IRQ-004   Thr-004
50  0        276489         0    206089         0    466018         0    481102         0    205546         0
51  1        318327     35487    388149     30024     94531     48382     83082     71078    388026     55730
52  2          3282    122584      4019    126527     28231    109012     23311     89309      4568     98739
53  3           940     11815       837      9863      6209     16227      6895     17196       910      9780
54  4           444     17287       424     11574      2097     38443      2169     36736       462     13476
55  5           206     43291       255     25581      1223    101908      1304    101137       236     28913
56  6           132    101501        96     64584       635    213774       757    215471        99     73453
57  7            74    169347        65    124758       350     57466       441     53639        69    148573
58  8            53     85183        31    156751       229      9052       306      9026        39    139907
59  9            22     10387        12     42762       161      2554       225      2689        19     26192
60  10           13      1898         8      5770       114      1247       128      1405        13      3772
61  11            9       560         9       924        71       686        76       765         8       713
62  12            4       256         2       360        50       411        64       474         3       278
63  13            2       167         2       172        43       256        53       350         4       180
64  14            1        88         1       116        15       198        42       223         0       115
65  15            2        63         3        94        11       139        20       150         0        58
66  16            2        37         0        56         5        78        10       102         0        39
67  17            0        18         0        28         4        57         8        80         0        15
68  18            0         8         0        17         2        50         6        56         0        12
69  19            0         9         0         5         0        19         0        48         0        18
70  20            0         4         0         8         0        11         2        27         0         4
71  21            0         2         0         3         1         9         1        18         0         6
72  22            0         1         0         3         1         7         0         3         0         5
73  23            0         2         0         4         0         2         0         7         0         2
74  24            0         2         0         2         1         3         0         3         0         5
75  25            0         0         0         1         0         1         0         1         0         3
76  26            0         1         0         0         0         2         0         2         0         0
77  27            0         0         0         3         0         1         0         0         0         1
78  28            0         0         0         3         0         0         0         1         0         0
79  29            0         0         0         2         0         2         0         1         0         3
80  30            0         1         0         0         0         0         0         0         0         0
81  31            0         1         0         0         0         0         0         2         0         2
82  32            0         0         0         1         0         2         0         0         0         0
83  33            0         0         0         2         0         0         0         0         0         1
84  34            0         0         0         0         0         0         0         0         0         2
85  35            0         1         0         1         0         0         0         0         0         1
86  36            0         1         0         0         0         1         0         1         0         0
87  37            0         0         0         1         0         0         0         0         0         0
88  40            0         0         0         0         0         1         0         1         0         0
89  41            0         0         0         0         0         0         0         0         0         1
90  42            0         0         0         0         0         0         0         0         0         1
91  44            0         0         0         0         0         1         0         0         0         0
92  46            0         0         0         0         0         0         0         1         0         0
93  47            0         0         0         0         0         0         0         0         0         1
94  50            0         0         0         0         0         0         0         0         0         1
95  54            0         0         0         1         0         0         0         0         0         0
96  58            0         0         0         1         0         0         0         0         0         0
97  over:         0         0         0         0         0         0         0         0         0         0
98  count:   600002    600002    600002    600002    600002    600002    600002    600002    600002    600002
99  min:          0         1         0         1         0         1         0         1         0         1
100  avg:          0         5         0         5         0         4         0         4         0         5
101  max:         16        36        15        58        24        44        21        46        13        50
102
103SEE ALSO
104========
105**rtla-timerlat**\(1), **rtla-timerlat-top**\(1)
106
107*timerlat* tracer documentation: <https://www.kernel.org/doc/html/latest/trace/timerlat-tracer.html>
108
109AUTHOR
110======
111Written by Daniel Bristot de Oliveira <bristot@kernel.org>
112
113.. include:: common_appendix.rst
114