Perf -- Linux下的系统性能调优工具
在ubuntu 11.04 要装了这两个包才有的工具的那些命令的，我在软件中心中装的 apt-get install 也一样吧？ linux-tools linux-tools-common 这个工具不错可以统计很多硬件相关信息 “cpu cache命中" "分支预测" "指令周期"等信息。还可以监控指定的进程的函数调用计数信息等。桌面$ perf list
List of pre-defined events (to be used in -e):
cpu-cycles OR cycles [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] alignment-faults [Software event] emulation-faults [Software event]L1-dcache-loads [Hardware cache event]
L1-dcache-load-misses [Hardware cache event] L1-dcache-stores [Hardware cache event] L1-dcache-store-misses [Hardware cache event] L1-dcache-prefetches [Hardware cache event] L1-dcache-prefetch-misses [Hardware cache event] L1-icache-loads [Hardware cache event] L1-icache-load-misses [Hardware cache event] L1-icache-prefetches [Hardware cache event] L1-icache-prefetch-misses [Hardware cache event] LLC-loads [Hardware cache event] LLC-load-misses [Hardware cache event] LLC-stores [Hardware cache event] LLC-store-misses [Hardware cache event] LLC-prefetches [Hardware cache event] LLC-prefetch-misses [Hardware cache event] dTLB-loads [Hardware cache event] dTLB-load-misses [Hardware cache event] dTLB-stores [Hardware cache event] dTLB-store-misses [Hardware cache event] dTLB-prefetches [Hardware cache event] dTLB-prefetch-misses [Hardware cache event] iTLB-loads [Hardware cache event] iTLB-load-misses [Hardware cache event] branch-loads [Hardware cache event] branch-load-misses [Hardware cache event]rNNN (see 'perf list --help' on how to encode it) [Raw hardware event descript
mem:<addr>[:access] [Hardware breakpoint]
perf stat ./a.out
^C Performance counter stats for './a.out':9,044 cache-misses # 0.003 M/sec (scaled from 66.87%)
523,191 cache-references # 0.172 M/sec (scaled from 66.96%) 21,838,315 branch-misses # 6.678 % (scaled from 33.13%) 327,014,993 branches # 107.285 M/sec (scaled from 33.04%) 2,355,587,681 instructions # 0.349 IPC (scaled from 49.41%) 6,740,540,287 cycles # 2211.403 M/sec (scaled from 67.03%) 100 page-faults # 0.000 M/sec 30 CPU-migrations # 0.000 M/sec 482 context-switches # 0.000 M/sec 3048.082970 task-clock-msecs # 0.596 CPUs5.118230246 seconds time elapsed
桌面$ ps -ef
UID PID PPID C STIME TTY TIME CMD root 1 0 0 08:21 ? 00:00:00 /sbin/init root 2 0 0 08:21 ? 00:00:00 [kthreadd] root 3 2 0 08:21 ? 00:00:00 [ksoftirqd/0] root 5 2 0 08:21 ? 00:00:00 [kworker/u:0] root 6 2 0 08:21 ? 00:00:00 [migration/0] root 7 2 0 08:21 ? 00:00:00 [migration/1] root 9 2 0 08:21 ? 00:00:00 [ksoftirqd/1] root 10 2 0 08:21 ? 00:00:01 [kworker/0:1] 桌面$ perf top -c 1000 -p 5 Fatal: Permission error - are you root? Consider tweaking /proc/sys/kernel/perf_event_paranoid.桌面$ sudo perf top -c 1000 -p 5
[sudo] password for widebright:-------------------------------------------------------------------------------
PerfTop: 302 irqs/sec kernel:100.0% exact: 0.0% [1000 cycles], (target_pid: 5) -------------------------------------------------------------------------------samples pcnt function DSO
_______ _____ ________________________________ ________603.00 19.7% i915_gem_retire_requests_ring [i915]
352.00 11.5% kref_put [kernel] 250.00 8.2% __ticket_spin_lock [kernel] 184.00 6.0% i915_gem_object_move_to_inactive [i915] 143.00 4.7% kfree [kernel] 113.00 3.7% __ticket_spin_unlock [kernel] 102.00 3.3% find_busiest_group [kernel] 69.00 2.3% i915_gem_retire_work_handler [i915] 65.00 2.1% __slab_free [kernel] 64.00 2.1% mod_timer [kernel] 61.00 2.0% i915_gem_object_move_to_active [i915] 53.00 1.7% update_cfs_load [kernel] 52.00 1.7% process_one_work [kernel]=========================
PERF-STAT(1) perf Manual PERF-STAT(1)NAME
perf-stat - Run a command and gather performance counter statisticsSYNOPSIS
perf stat [-e <EVENT> | --event=EVENT] [-a] <command> perf stat [-e <EVENT> | --event=EVENT] [-a] — <command> [<options>]DESCRIPTION
This command runs a command and gathers performance counter statistics from it.OPTIONS
<command>... Any command you can specify in a shell.-e, --event=
Select the PMU event. Selection can be a symbolic event name (use perf list to list all events) or a raw PMU event (eventsel+umask) in the form of rNNN where NNN is a hexadecimal event descriptor.-i, --no-inherit
child tasks do not inherit counters-p, --pid=<pid>
stat events on existing process id-t, --tid=<tid>
stat events on existing thread id-a, --all-cpus
system-wide collection from all CPUs-c, --scale
scale/normalize counter values-r, --repeat=<n>
repeat command and print average + stddev (max: 100)-B, --big-num
print large numbers with thousands' separators according to locale-C, --cpu=
Count only on the list of CPUs provided. Multiple CPUs can be provided as a comma-separated list with no space: 0,1. Ranges of CPUs are specified with -: 0-2. In per-thread mode, this option is ignored. The -a option is still necessary to activate system-wide monitoring. Default is to count on all CPUs.-A, --no-aggr
Do not aggregate counts across all monitored CPUs in system-wide mode (-a). This option is only valid in system-wide mode.-n, --null
null run - don’t start any counters-v, --verbose
be more verbose (show counter open errors, etc)-x SEP, --field-separator SEP
print counts using a CSV-style output to make it easy to import directly into spreadsheets. Columns are separated by the string specified in SEP.EXAMPLES
$ perf stat — make -jPerformance counter stats for 'make -j':
8117.370256 task clock ticks # 11.281 CPU utilization factor
678 context switches # 0.000 M/sec 133 CPU migrations # 0.000 M/sec 235724 pagefaults # 0.029 M/sec 24821162526 CPU cycles # 3057.784 M/sec 18687303457 instructions # 2302.138 M/sec 172158895 cache references # 21.209 M/sec 27075259 cache misses # 3.335 M/secWall-clock time elapsed: 719.554352 msecs
SEE ALSO
perf-top(1), perf-list(1)