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v5.4
  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.
 72-o::
 73--output=<path>::
 74        Output file name.
 
 75--host::
 76        Collect host side performance profile.
 77--guest::
 78        Collect guest side performance profile.
 79--guestmount=<path>::
 80	Guest os root file system mount directory. Users mounts guest os
 81        root directories under <path> by a specific filesystem access method,
 82	typically, sshfs. For example, start 2 guest os. The one's pid is 8888
 83	and the other's is 9999.
 84        #mkdir ~/guestmount; cd ~/guestmount
 85        #sshfs -o allow_other,direct_io -p 5551 localhost:/ 8888/
 86        #sshfs -o allow_other,direct_io -p 5552 localhost:/ 9999/
 87        #perf kvm --host --guest --guestmount=~/guestmount top
 88--guestkallsyms=<path>::
 89        Guest os /proc/kallsyms file copy. 'perf' kvm' reads it to get guest
 90	kernel symbols. Users copy it out from guest os.
 91--guestmodules=<path>::
 92	Guest os /proc/modules file copy. 'perf' kvm' reads it to get guest
 93	kernel module information. Users copy it out from guest os.
 94--guestvmlinux=<path>::
 95	Guest os kernel vmlinux.
 96-v::
 97--verbose::
 98	Be more verbose (show counter open errors, etc).
 99
100STAT REPORT OPTIONS
101-------------------
102--vcpu=<value>::
103       analyze events which occur on this vcpu. (default: all vcpus)
104
105--event=<value>::
106       event to be analyzed. Possible values: vmexit, mmio (x86 only),
107       ioport (x86 only). (default: vmexit)
108-k::
109--key=<value>::
110       Sorting key. Possible values: sample (default, sort by samples
111       number), time (sort by average time).
 
 
 
112-p::
113--pid=::
114    Analyze events only for given process ID(s) (comma separated list).
115
116STAT LIVE OPTIONS
117-----------------
118-d::
119--display::
120        Time in seconds between display updates
121
122-m::
123--mmap-pages=::
124    Number of mmap data pages (must be a power of two) or size
125    specification with appended unit character - B/K/M/G. The
126    size is rounded up to have nearest pages power of two value.
127
128-a::
129--all-cpus::
130        System-wide collection from all CPUs.
131
132-p::
133--pid=::
134    Analyze events only for given process ID(s) (comma separated list).
135
136--vcpu=<value>::
137       analyze events which occur on this vcpu. (default: all vcpus)
138
139
140--event=<value>::
141       event to be analyzed. Possible values: vmexit,
142       mmio (x86 only), ioport (x86 only).
143       (default: vmexit)
144
145-k::
146--key=<value>::
147       Sorting key. Possible values: sample (default, sort by samples
148       number), time (sort by average time).
149
150--duration=<value>::
151       Show events other than HLT (x86 only) or Wait state (s390 only)
152       that take longer than duration usecs.
153
154--proc-map-timeout::
155	When processing pre-existing threads /proc/XXX/mmap, it may take
156	a long time, because the file may be huge. A time out is needed
157	in such cases.
158	This option sets the time out limit. The default value is 500 ms.
159
160SEE ALSO
161--------
162linkperf:perf-top[1], linkperf:perf-record[1], linkperf:perf-report[1],
163linkperf:perf-diff[1], linkperf:perf-buildid-list[1],
164linkperf:perf-stat[1]
v6.8
  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 sample, percent_sample, time, percent_time, max_t, min_t, mean_t.
 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--stdio:: Use the stdio interface.
 86
 
 
 
 
 
 
 
 
 
 
 87-v::
 88--verbose::
 89	Be more verbose (show counter open errors, etc).
 90
 91STAT REPORT OPTIONS
 92-------------------
 93--vcpu=<value>::
 94       analyze events which occur on this vcpu. (default: all vcpus)
 95
 96--event=<value>::
 97       event to be analyzed. Possible values: vmexit, mmio (x86 only),
 98       ioport (x86 only). (default: vmexit)
 99-k::
100--key=<value>::
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
105       (sort by mean time).
106-p::
107--pid=::
108    Analyze events only for given process ID(s) (comma separated list).
109
110STAT LIVE OPTIONS
111-----------------
112-d::
113--display::
114        Time in seconds between display updates
115
116-m::
117--mmap-pages=::
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.
121
122-a::
123--all-cpus::
124        System-wide collection from all CPUs.
125
126-p::
127--pid=::
128    Analyze events only for given process ID(s) (comma separated list).
129
130--vcpu=<value>::
131       analyze events which occur on this vcpu. (default: all vcpus)
132
133
134--event=<value>::
135       event to be analyzed. Possible values: vmexit,
136       mmio (x86 only), ioport (x86 only).
137       (default: vmexit)
138
139-k::
140--key=<value>::
141       Sorting key. Possible values: sample (default, sort by samples
142       number), time (sort by average time).
143
144--duration=<value>::
145       Show events other than HLT (x86 only) or Wait state (s390 only)
146       that take longer than duration usecs.
147
148--proc-map-timeout::
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
151	in such cases.
152	This option sets the time out limit. The default value is 500 ms.
153
154SEE ALSO
155--------
156linkperf:perf-top[1], linkperf:perf-record[1], linkperf:perf-report[1],
157linkperf:perf-diff[1], linkperf:perf-buildid-list[1],
158linkperf:perf-stat[1]