PERF-KVM(1) perf Manual PERF-KVM(1)NAMEperf-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}
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.
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)
--events=<value>
events 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).
SEE ALSOperf-top(1), perf-record(1), perf-report(1), perf-diff(1), perf-
buildid-list(1), perf-stat(1)perf 11/26/2013 PERF-KVM(1)
