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c0ee1d5ae8
Currently perf stat shows some metrics (like IPC) for defined events.
But when no aggregation mode is used (-A option), it shows incorrect
values since it used a value from a different cpu.
Before:
$ perf stat -aA -e cycles,instructions sleep 1
Performance counter stats for 'system wide':
CPU0 116,057,380 cycles
CPU1 86,084,722 cycles
CPU2 99,423,125 cycles
CPU3 98,272,994 cycles
CPU0 53,369,217 instructions # 0.46 insn per cycle
CPU1 33,378,058 instructions # 0.29 insn per cycle
CPU2 58,150,086 instructions # 0.50 insn per cycle
CPU3 40,029,703 instructions # 0.34 insn per cycle
1.001816971 seconds time elapsed
So the IPC for CPU1 should be 0.38 (= 33,378,058 / 86,084,722)
but it was 0.29 (= 33,378,058 / 116,057,380) and so on.
After:
$ perf stat -aA -e cycles,instructions sleep 1
Performance counter stats for 'system wide':
CPU0 109,621,384 cycles
CPU1 159,026,454 cycles
CPU2 99,460,366 cycles
CPU3 124,144,142 cycles
CPU0 44,396,706 instructions # 0.41 insn per cycle
CPU1 120,195,425 instructions # 0.76 insn per cycle
CPU2 44,763,978 instructions # 0.45 insn per cycle
CPU3 69,049,079 instructions # 0.56 insn per cycle
1.001910444 seconds time elapsed
Fixes:
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|---|---|---|
| .. | ||
| accounting | ||
| arch | ||
| bootconfig | ||
| bpf | ||
| build | ||
| cgroup | ||
| debugging | ||
| edid | ||
| firewire | ||
| firmware | ||
| gpio | ||
| hv | ||
| iio | ||
| include | ||
| io_uring | ||
| kvm/kvm_stat | ||
| laptop | ||
| leds | ||
| lib | ||
| memory-model | ||
| objtool | ||
| pci | ||
| pcmcia | ||
| perf | ||
| power | ||
| scripts | ||
| spi | ||
| testing | ||
| thermal/tmon | ||
| time | ||
| usb | ||
| virtio | ||
| vm | ||
| wmi | ||
| Makefile | ||