diff options
Diffstat (limited to '')
| -rw-r--r-- | tools/perf/Documentation/perf-kvm.txt | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/tools/perf/Documentation/perf-kvm.txt b/tools/perf/Documentation/perf-kvm.txt new file mode 100644 index 000000000..cf95baef7 --- /dev/null +++ b/tools/perf/Documentation/perf-kvm.txt @@ -0,0 +1,165 @@ +perf-kvm(1) +=========== + +NAME +---- +perf-kvm - Tool to trace/measure kvm guest os + +SYNOPSIS +-------- +[verse] +'perf kvm' [--host] [--guest] [--guestmount=<path> + [--guestkallsyms=<path> --guestmodules=<path> | --guestvmlinux=<path>]] + {top|record|report|diff|buildid-list} [<options>] +'perf kvm' [--host] [--guest] [--guestkallsyms=<path> --guestmodules=<path> + | --guestvmlinux=<path>] {top|record|report|diff|buildid-list|stat} [<options>] +'perf kvm stat [record|report|live] [<options>] + +DESCRIPTION +----------- +There are a couple of variants of perf kvm: + + 'perf kvm [options] top <command>' to generates and displays + a performance counter profile of guest os in realtime + of an arbitrary workload. + + 'perf kvm record <command>' to record the performance counter profile + of an arbitrary workload and save it into a perf data file. We set the + default behavior of perf kvm as --guest, so if neither --host nor --guest + is input, the perf data file name is perf.data.guest. If --host is input, + the perf data file name is perf.data.kvm. If you want to record data into + perf.data.host, please input --host --no-guest. The behaviors are shown as + following: + Default('') -> perf.data.guest + --host -> perf.data.kvm + --guest -> perf.data.guest + --host --guest -> perf.data.kvm + --host --no-guest -> perf.data.host + + 'perf kvm report' to display the performance counter profile information + recorded via perf kvm record. + + 'perf kvm diff' to displays the performance difference amongst two perf.data + files captured via perf record. + + 'perf kvm buildid-list' to display the buildids found in a perf data file, + so that other tools can be used to fetch packages with matching symbol tables + for use by perf report. As buildid is read from /sys/kernel/notes in os, then + if you want to list the buildid for guest, please make sure your perf data file + was captured with --guestmount in perf kvm record. + + 'perf kvm stat <command>' to run a command and gather performance counter + statistics. + Especially, perf 'kvm stat record/report' generates a statistical analysis + of KVM events. Currently, vmexit, mmio (x86 only) and ioport (x86 only) + events are supported. 'perf kvm stat record <command>' records kvm events + and the events between start and end <command>. + And this command produces a file which contains tracing results of kvm + events. + + 'perf kvm stat report' reports statistical data which includes events + handled time, samples, and so on. + + 'perf kvm stat live' reports statistical data in a live mode (similar to + record + report but with statistical data updated live at a given display + rate). + +OPTIONS +------- +-i:: +--input=<path>:: + Input file name, for the 'report', 'diff' and 'buildid-list' subcommands. +-o:: +--output=<path>:: + Output file name, for the 'record' subcommand. Doesn't work with 'report', + just redirect the output to a file when using 'report'. +--host:: + Collect host side performance profile. +--guest:: + Collect guest side performance profile. +--guestmount=<path>:: + Guest os root file system mount directory. Users mounts guest os + root directories under <path> by a specific filesystem access method, + typically, sshfs. For example, start 2 guest os. The one's pid is 8888 + and the other's is 9999. + #mkdir ~/guestmount; cd ~/guestmount + #sshfs -o allow_other,direct_io -p 5551 localhost:/ 8888/ + #sshfs -o allow_other,direct_io -p 5552 localhost:/ 9999/ + #perf kvm --host --guest --guestmount=~/guestmount top +--guestkallsyms=<path>:: + Guest os /proc/kallsyms file copy. 'perf' kvm' reads it to get guest + kernel symbols. Users copy it out from guest os. +--guestmodules=<path>:: + Guest os /proc/modules file copy. 'perf' kvm' reads it to get guest + kernel module information. Users copy it out from guest os. +--guestvmlinux=<path>:: + Guest os kernel vmlinux. +-v:: +--verbose:: + Be more verbose (show counter open errors, etc). + +STAT REPORT OPTIONS +------------------- +--vcpu=<value>:: + analyze events which occur on this vcpu. (default: all vcpus) + +--event=<value>:: + event to be analyzed. Possible values: vmexit, mmio (x86 only), + ioport (x86 only). (default: vmexit) +-k:: +--key=<value>:: + Sorting key. Possible values: sample (default, sort by samples + number), time (sort by average time). +-p:: +--pid=:: + Analyze events only for given process ID(s) (comma separated list). + +STAT LIVE OPTIONS +----------------- +-d:: +--display:: + Time in seconds between display updates + +-m:: +--mmap-pages=:: + Number of mmap data pages (must be a power of two) or size + specification with appended unit character - B/K/M/G. The + size is rounded up to have nearest pages power of two value. + +-a:: +--all-cpus:: + System-wide collection from all CPUs. + +-p:: +--pid=:: + Analyze events only for given process ID(s) (comma separated list). + +--vcpu=<value>:: + analyze events which occur on this vcpu. (default: all vcpus) + + +--event=<value>:: + event to be analyzed. Possible values: vmexit, + mmio (x86 only), ioport (x86 only). + (default: vmexit) + +-k:: +--key=<value>:: + Sorting key. Possible values: sample (default, sort by samples + number), time (sort by average time). + +--duration=<value>:: + Show events other than HLT (x86 only) or Wait state (s390 only) + that take longer than duration usecs. + +--proc-map-timeout:: + When processing pre-existing threads /proc/XXX/mmap, it may take + a long time, because the file may be huge. A time out is needed + in such cases. + This option sets the time out limit. The default value is 500 ms. + +SEE ALSO +-------- +linkperf:perf-top[1], linkperf:perf-record[1], linkperf:perf-report[1], +linkperf:perf-diff[1], linkperf:perf-buildid-list[1], +linkperf:perf-stat[1] |