1perf-kvm(1) 2=========== 3 4NAME 5---- 6perf-kvm - Tool to trace/measure kvm guest os 7 8SYNOPSIS 9-------- 10[verse] 11'perf kvm' [--host] [--guest] [--guestmount=<path> 12 [--guestkallsyms=<path> --guestmodules=<path> | --guestvmlinux=<path>]] 13 {top|record|report|diff|buildid-list} 14'perf kvm' [--host] [--guest] [--guestkallsyms=<path> --guestmodules=<path> 15 | --guestvmlinux=<path>] {top|record|report|diff|buildid-list|stat} 16 17DESCRIPTION 18----------- 19There are a couple of variants of perf kvm: 20 21 'perf kvm [options] top <command>' to generates and displays 22 a performance counter profile of guest os in realtime 23 of an arbitrary workload. 24 25 'perf kvm record <command>' to record the performance counter profile 26 of an arbitrary workload and save it into a perf data file. If both 27 --host and --guest are input, the perf data file name is perf.data.kvm. 28 If there is no --host but --guest, the file name is perf.data.guest. 29 If there is no --guest but --host, the file name is perf.data.host. 30 31 'perf kvm report' to display the performance counter profile information 32 recorded via perf kvm record. 33 34 'perf kvm diff' to displays the performance difference amongst two perf.data 35 files captured via perf record. 36 37 'perf kvm buildid-list' to display the buildids found in a perf data file, 38 so that other tools can be used to fetch packages with matching symbol tables 39 for use by perf report. 40 41 'perf kvm stat <command>' to run a command and gather performance counter 42 statistics. 43 Especially, perf 'kvm stat record/report' generates a statistical analysis 44 of KVM events. Currently, vmexit, mmio and ioport events are supported. 45 'perf kvm stat record <command>' records kvm events and the events between 46 start and end <command>. 47 And this command produces a file which contains tracing results of kvm 48 events. 49 50 'perf kvm stat report' reports statistical data which includes events 51 handled time, samples, and so on. 52 53OPTIONS 54------- 55-i:: 56--input=:: 57 Input file name. 58-o:: 59--output:: 60 Output file name. 61--host=:: 62 Collect host side performance profile. 63--guest=:: 64 Collect guest side performance profile. 65--guestmount=<path>:: 66 Guest os root file system mount directory. Users mounts guest os 67 root directories under <path> by a specific filesystem access method, 68 typically, sshfs. For example, start 2 guest os. The one's pid is 8888 69 and the other's is 9999. 70 #mkdir ~/guestmount; cd ~/guestmount 71 #sshfs -o allow_other,direct_io -p 5551 localhost:/ 8888/ 72 #sshfs -o allow_other,direct_io -p 5552 localhost:/ 9999/ 73 #perf kvm --host --guest --guestmount=~/guestmount top 74--guestkallsyms=<path>:: 75 Guest os /proc/kallsyms file copy. 'perf' kvm' reads it to get guest 76 kernel symbols. Users copy it out from guest os. 77--guestmodules=<path>:: 78 Guest os /proc/modules file copy. 'perf' kvm' reads it to get guest 79 kernel module information. Users copy it out from guest os. 80--guestvmlinux=<path>:: 81 Guest os kernel vmlinux. 82 83STAT REPORT OPTIONS 84------------------- 85--vcpu=<value>:: 86 analyze events which occures on this vcpu. (default: all vcpus) 87 88--events=<value>:: 89 events to be analyzed. Possible values: vmexit, mmio, ioport. 90 (default: vmexit) 91-k:: 92--key=<value>:: 93 Sorting key. Possible values: sample (default, sort by samples 94 number), time (sort by average time). 95 96SEE ALSO 97-------- 98linkperf:perf-top[1], linkperf:perf-record[1], linkperf:perf-report[1], 99linkperf:perf-diff[1], linkperf:perf-buildid-list[1], 100linkperf:perf-stat[1] 101