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 11/21/2013 PERF-KVM(1)