xref: /linux/tools/perf/Documentation/perf-kvm.txt (revision 69bfec7548f4c1595bac0e3ddfc0458a5af31f4c)
1perf-kvm(1)
2===========
3
4NAME
5----
6perf-kvm - Tool to trace/measure kvm guest os
7
8SYNOPSIS
9--------
10[verse]
11'perf kvm' [--host] [--guest] [--guestmount=<path>
12	[--guestkallsyms=<path> --guestmodules=<path> | --guestvmlinux=<path>]]
13	{top|record|report|diff|buildid-list} [<options>]
14'perf kvm' [--host] [--guest] [--guestkallsyms=<path> --guestmodules=<path>
15	| --guestvmlinux=<path>] {top|record|report|diff|buildid-list|stat} [<options>]
16'perf kvm stat [record|report|live] [<options>]
17
18DESCRIPTION
19-----------
20There are a couple of variants of perf kvm:
21
22  'perf kvm [options] top <command>' to generates and displays
23  a performance counter profile of guest os in realtime
24  of an arbitrary workload.
25
26  'perf kvm record <command>' to record the performance counter profile
27  of an arbitrary workload and save it into a perf data file. We set the
28  default behavior of perf kvm as --guest, so if neither --host nor --guest
29  is input, the perf data file name is perf.data.guest. If --host is input,
30  the perf data file name is perf.data.kvm. If you want to record data into
31  perf.data.host, please input --host --no-guest. The behaviors are shown as
32  following:
33    Default('')         ->  perf.data.guest
34    --host              ->  perf.data.kvm
35    --guest             ->  perf.data.guest
36    --host --guest      ->  perf.data.kvm
37    --host --no-guest   ->  perf.data.host
38
39  'perf kvm report' to display the performance counter profile information
40  recorded via perf kvm record.
41
42  'perf kvm diff' to displays the performance difference amongst two perf.data
43  files captured via perf record.
44
45  'perf kvm buildid-list' to  display the buildids found in a perf data file,
46  so that other tools can be used to fetch packages with matching symbol tables
47  for use by perf report. As buildid is read from /sys/kernel/notes in os, then
48  if you want to list the buildid for guest, please make sure your perf data file
49  was captured with --guestmount in perf kvm record.
50
51  'perf kvm stat <command>' to run a command and gather performance counter
52  statistics.
53  Especially, perf 'kvm stat record/report' generates a statistical analysis
54  of KVM events. Currently, vmexit, mmio (x86 only) and ioport (x86 only)
55  events are supported. 'perf kvm stat record <command>' records kvm events
56  and the events between start and end <command>.
57  And this command produces a file which contains tracing results of kvm
58  events.
59
60  'perf kvm stat report' reports statistical data which includes events
61  handled time, samples, and so on.
62
63  'perf kvm stat live' reports statistical data in a live mode (similar to
64  record + report but with statistical data updated live at a given display
65  rate).
66
67OPTIONS
68-------
69-i::
70--input=<path>::
71        Input file name, for the 'report', 'diff' and 'buildid-list' subcommands.
72-o::
73--output=<path>::
74        Output file name, for the 'record' subcommand. Doesn't work with 'report',
75        just redirect the output to a file when using 'report'.
76--host::
77        Collect host side performance profile.
78--guest::
79        Collect guest side performance profile.
80
81:GMEXAMPLECMD: kvm --host --guest
82:GMEXAMPLESUBCMD: top
83include::guest-files.txt[]
84
85-v::
86--verbose::
87	Be more verbose (show counter open errors, etc).
88
89STAT REPORT OPTIONS
90-------------------
91--vcpu=<value>::
92       analyze events which occur on this vcpu. (default: all vcpus)
93
94--event=<value>::
95       event to be analyzed. Possible values: vmexit, mmio (x86 only),
96       ioport (x86 only). (default: vmexit)
97-k::
98--key=<value>::
99       Sorting key. Possible values: sample (default, sort by samples
100       number), time (sort by average time).
101-p::
102--pid=::
103    Analyze events only for given process ID(s) (comma separated list).
104
105STAT LIVE OPTIONS
106-----------------
107-d::
108--display::
109        Time in seconds between display updates
110
111-m::
112--mmap-pages=::
113    Number of mmap data pages (must be a power of two) or size
114    specification with appended unit character - B/K/M/G. The
115    size is rounded up to have nearest pages power of two value.
116
117-a::
118--all-cpus::
119        System-wide collection from all CPUs.
120
121-p::
122--pid=::
123    Analyze events only for given process ID(s) (comma separated list).
124
125--vcpu=<value>::
126       analyze events which occur on this vcpu. (default: all vcpus)
127
128
129--event=<value>::
130       event to be analyzed. Possible values: vmexit,
131       mmio (x86 only), ioport (x86 only).
132       (default: vmexit)
133
134-k::
135--key=<value>::
136       Sorting key. Possible values: sample (default, sort by samples
137       number), time (sort by average time).
138
139--duration=<value>::
140       Show events other than HLT (x86 only) or Wait state (s390 only)
141       that take longer than duration usecs.
142
143--proc-map-timeout::
144	When processing pre-existing threads /proc/XXX/mmap, it may take
145	a long time, because the file may be huge. A time out is needed
146	in such cases.
147	This option sets the time out limit. The default value is 500 ms.
148
149SEE ALSO
150--------
151linkperf:perf-top[1], linkperf:perf-record[1], linkperf:perf-report[1],
152linkperf:perf-diff[1], linkperf:perf-buildid-list[1],
153linkperf:perf-stat[1]
154