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@@ -93,14 +93,14 @@ By specifying the -a switch and analysing sleep, the system-wide events
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for a duration of time can be examined.
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$ perf stat -a \
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- -e kmem:mm_page_alloc -e kmem:mm_page_free_direct \
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- -e kmem:mm_pagevec_free \
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+ -e kmem:mm_page_alloc -e kmem:mm_page_free \
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+ -e kmem:mm_page_free_batched \
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sleep 10
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Performance counter stats for 'sleep 10':
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9630 kmem:mm_page_alloc
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- 2143 kmem:mm_page_free_direct
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- 7424 kmem:mm_pagevec_free
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+ 2143 kmem:mm_page_free
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+ 7424 kmem:mm_page_free_batched
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10.002577764 seconds time elapsed
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@@ -119,15 +119,15 @@ basis using set_ftrace_pid.
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Events can be activated and tracked for the duration of a process on a local
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basis using PCL such as follows.
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- $ perf stat -e kmem:mm_page_alloc -e kmem:mm_page_free_direct \
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- -e kmem:mm_pagevec_free ./hackbench 10
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+ $ perf stat -e kmem:mm_page_alloc -e kmem:mm_page_free \
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+ -e kmem:mm_page_free_batched ./hackbench 10
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Time: 0.909
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Performance counter stats for './hackbench 10':
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17803 kmem:mm_page_alloc
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- 12398 kmem:mm_page_free_direct
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- 4827 kmem:mm_pagevec_free
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+ 12398 kmem:mm_page_free
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+ 4827 kmem:mm_page_free_batched
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0.973913387 seconds time elapsed
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@@ -146,8 +146,8 @@ to know what the standard deviation is. By and large, this is left to the
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performance analyst to do it by hand. In the event that the discrete event
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occurrences are useful to the performance analyst, then perf can be used.
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- $ perf stat --repeat 5 -e kmem:mm_page_alloc -e kmem:mm_page_free_direct
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- -e kmem:mm_pagevec_free ./hackbench 10
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+ $ perf stat --repeat 5 -e kmem:mm_page_alloc -e kmem:mm_page_free
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+ -e kmem:mm_page_free_batched ./hackbench 10
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Time: 0.890
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Time: 0.895
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Time: 0.915
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@@ -157,8 +157,8 @@ occurrences are useful to the performance analyst, then perf can be used.
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Performance counter stats for './hackbench 10' (5 runs):
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16630 kmem:mm_page_alloc ( +- 3.542% )
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- 11486 kmem:mm_page_free_direct ( +- 4.771% )
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- 4730 kmem:mm_pagevec_free ( +- 2.325% )
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+ 11486 kmem:mm_page_free ( +- 4.771% )
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+ 4730 kmem:mm_page_free_batched ( +- 2.325% )
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0.982653002 seconds time elapsed ( +- 1.448% )
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@@ -168,15 +168,15 @@ aggregation of discrete events, then a script would need to be developed.
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Using --repeat, it is also possible to view how events are fluctuating over
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time on a system-wide basis using -a and sleep.
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- $ perf stat -e kmem:mm_page_alloc -e kmem:mm_page_free_direct \
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- -e kmem:mm_pagevec_free \
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+ $ perf stat -e kmem:mm_page_alloc -e kmem:mm_page_free \
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+ -e kmem:mm_page_free_batched \
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-a --repeat 10 \
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sleep 1
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Performance counter stats for 'sleep 1' (10 runs):
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1066 kmem:mm_page_alloc ( +- 26.148% )
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- 182 kmem:mm_page_free_direct ( +- 5.464% )
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- 890 kmem:mm_pagevec_free ( +- 30.079% )
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+ 182 kmem:mm_page_free ( +- 5.464% )
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+ 890 kmem:mm_page_free_batched ( +- 30.079% )
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1.002251757 seconds time elapsed ( +- 0.005% )
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@@ -220,8 +220,8 @@ were generating events within the kernel. To begin this sort of analysis, the
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data must be recorded. At the time of writing, this required root:
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$ perf record -c 1 \
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- -e kmem:mm_page_alloc -e kmem:mm_page_free_direct \
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- -e kmem:mm_pagevec_free \
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+ -e kmem:mm_page_alloc -e kmem:mm_page_free \
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+ -e kmem:mm_page_free_batched \
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./hackbench 10
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Time: 0.894
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[ perf record: Captured and wrote 0.733 MB perf.data (~32010 samples) ]
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@@ -260,8 +260,8 @@ noticed that X was generating an insane amount of page allocations so let's look
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at it:
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$ perf record -c 1 -f \
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- -e kmem:mm_page_alloc -e kmem:mm_page_free_direct \
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- -e kmem:mm_pagevec_free \
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+ -e kmem:mm_page_alloc -e kmem:mm_page_free \
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+ -e kmem:mm_page_free_batched \
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-p `pidof X`
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This was interrupted after a few seconds and
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