PERF-KVM(1)							    perf Manual 						       PERF-KVM(1)

NAME
perf-kvm - Tool to trace/measure kvm guest os SYNOPSIS
perf kvm [--host] [--guest] [--guestmount=<path> [--guestkallsyms=<path> --guestmodules=<path> | --guestvmlinux=<path>]] {top|record|report|diff|buildid-list} perf kvm [--host] [--guest] [--guestkallsyms=<path> --guestmodules=<path> | --guestvmlinux=<path>] {top|record|report|diff|buildid-list|stat} '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. If both --host and --guest are input, the perf data file name is perf.data.kvm. If there is no --host but --guest, the file name is perf.data.guest. If there is no --guest but --host, the file name is 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. '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 and ioport 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= Input file name. -o, --output Output file name. --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. STAT REPORT OPTIONS
--vcpu=<value> analyze events which occures on this vcpu. (default: all vcpus) --event=<value> event to be analyzed. Possible values: vmexit, mmio, ioport. (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. -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 occures on this vcpu. (default: all vcpus) --event=<value> event to be analyzed. Possible values: vmexit, mmio, ioport. (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 that take longer than duration usecs. SEE ALSO
perf-top(1), perf-record(1), perf-report(1), perf-diff(1), perf-buildid-list(1), perf-stat(1) perf 06/30/2014 PERF-KVM(1)

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