PERF\-KVM

Section: Misc. Reference Manual Pages (1)
Updated: 10/16/2012
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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}

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.

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 onecqs pid is 8888 and the othercqs 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.