6 perf-kvm - Tool to trace/measure kvm guest os
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>]
20 There are a couple of variants of perf kvm:
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.
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
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
39 'perf kvm report' to display the performance counter profile information
40 recorded via perf kvm record.
42 'perf kvm diff' to displays the performance difference amongst two perf.data
43 files captured via perf record.
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.
51 'perf kvm stat <command>' to run a command and gather performance counter
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
60 'perf kvm stat report' reports statistical data which includes events
61 handled sample, percent_sample, time, percent_time, max_t, min_t, mean_t.
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
71 Input file name, for the 'report', 'diff' and 'buildid-list' subcommands.
74 Output file name, for the 'record' subcommand. Doesn't work with 'report',
75 just redirect the output to a file when using 'report'.
77 Collect host side performance profile.
79 Collect guest side performance profile.
81 :GMEXAMPLECMD: kvm --host --guest
83 include::guest-files.txt[]
85 --stdio:: Use the stdio interface.
89 Be more verbose (show counter open errors, etc).
94 analyze events which occur on this vcpu. (default: all vcpus)
97 event to be analyzed. Possible values: vmexit, mmio (x86 only),
98 ioport (x86 only). (default: vmexit)
101 Sorting key. Possible values: sample (default, sort by samples
102 number), percent_sample (sort by sample percentage), time
103 (sort by average time), precent_time (sort by time percentage),
104 max_t (sort by maximum time), min_t (sort by minimum time), mean_t
108 Analyze events only for given process ID(s) (comma separated list).
114 Time in seconds between display updates
118 Number of mmap data pages (must be a power of two) or size
119 specification with appended unit character - B/K/M/G. The
120 size is rounded up to have nearest pages power of two value.
124 System-wide collection from all CPUs.
128 Analyze events only for given process ID(s) (comma separated list).
131 analyze events which occur on this vcpu. (default: all vcpus)
135 event to be analyzed. Possible values: vmexit,
136 mmio (x86 only), ioport (x86 only).
141 Sorting key. Possible values: sample (default, sort by samples
142 number), time (sort by average time).
145 Show events other than HLT (x86 only) or Wait state (s390 only)
146 that take longer than duration usecs.
149 When processing pre-existing threads /proc/XXX/mmap, it may take
150 a long time, because the file may be huge. A time out is needed
152 This option sets the time out limit. The default value is 500 ms.
156 linkperf:perf-top[1], linkperf:perf-record[1], linkperf:perf-report[1],
157 linkperf:perf-diff[1], linkperf:perf-buildid-list[1],
158 linkperf:perf-stat[1]