How to install perf ( kernel performance monitor ) on Ubuntu , CentOS

[ install perf on Ubuntu 12.04 ]

# tail -1 /etc/lsb-release DISTRIB_DESCRIPTION="Ubuntu 12.04 LTS" # uname -ri 3.2.0-25-generic x86_64

install

# apt-get install linux-tools -y

monitor a chromium-browser process.

fly chromium-browser via perf like this

on GUI , issue the following command

# perf record chromium-browser

nnn, there appears a waning message.. , kernel pointer ??

Kernel address maps (/proc/{kallsyms,modules}) were restricted.                                                                         Check /proc/sys/kernel/kptr_restrict before running 'perf record'.

to solve this:

# cat /proc/sys/kernel/kptr_restrict 1 # echo 0 > /proc/sys/kernel/kptr_restrict # cat /proc/sys/kernel/kptr_restrict 0 # cat /proc/kallsyms  | head -10 0000000000000000 D irq_stack_union 0000000000000000 D __per_cpu_start 0000000000004000 D gdt_page 0000000000005000 d exception_stacks 000000000000b000 d tlb_vector_offset 000000000000b080 d cpu_loops_per_jiffy 000000000000b0c0 D xen_vcpu_info 000000000000b100 D xen_vcpu 000000000000b108 d idt_desc 000000000000b118 d xen_cr0_value

try again.

Okay , there are no warning messages.

check the result file

$ perf report Events: 3K cycles 73.37%  chromium-browse  [unknown]                [.] 0x7f613588d718  2.80%  chromium-browse  [kernel.kallsyms]        [k] native_write_msr_safe  1.25%  chromium-browse  [kernel.kallsyms]        [k] page_fault  1.02%  chromium-browse  libfreebl3.so            [.] 0x27d5e <snip>

you can specify events you’d like to collect.

# perf list List of pre-defined events (to be used in -e):  cpu-cycles OR cycles                               [Hardware event]  stalled-cycles-frontend OR idle-cycles-frontend    [Hardware event]  stalled-cycles-backend OR idle-cycles-backend      [Hardware event]  instructions                                       [Hardware event]  cache-references                                   [Hardware event]  cache-misses                                       [Hardware event]  branch-instructions OR branches                    [Hardware event]  branch-misses                                      [Hardware event]  bus-cycles                                         [Hardware event]  cpu-clock                                          [Software event]  task-clock                                         [Software event]  page-faults OR faults                              [Software event]  minor-faults                                       [Software event]  major-faults                                       [Software event]  context-switches OR cs                             [Software event]  cpu-migrations OR migrations                       [Software event]

$ perf record -e cpu-cycles -e cpu-clock -e context-switches chromium-browser

$ perf report

perf stat

$ perf stat chromium-browser Performance counter stats for 'chromium-browser':       2349.438123 task-clock                #    0.211 CPUs utilized                       6,912 context-switches          #    0.003 M/sec                                 635 CPU-migrations            #    0.000 M/sec                              87,726 page-faults               #    0.037 M/sec                       4,824,461,601 cycles                    #    2.053 GHz                     [83.95%]     2,375,916,048 stalled-cycles-frontend   #   49.25% frontend cycles idle    [82.50%]     1,467,114,781 stalled-cycles-backend    #   30.41% backend  cycles idle    [67.95%]     5,208,469,775 instructions              #    1.08  insns per cycle                                                     #    0.46  stalled cycles per insn [83.95%]     1,091,803,683 branches                  #  464.708 M/sec                   [82.98%]        31,296,254 branch-misses             #    2.87% of all branches         [83.44%]      11.149857740 seconds time elapsed

[ install perf on CentOS6 ]

# cat /etc/centos-release CentOS release 6.2 (Final) # uname -ri 2.6.32-220.17.1.el6.x86_64 x86_64 # yum install -y perf