brendangregg / FlameGraph

Stack trace visualizer
http://www.brendangregg.com/flamegraphs.html
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Capturing stacks on Amazon Linux 2 kernel 4.14 and 5.10 #306

Open RamaMalladiAWS opened 1 year ago

RamaMalladiAWS commented 1 year ago

I am trying to capture stacks from a perf.data file collected on Amazon Linux 2 kernel 4.14 and 5.10.

I find that the perf.data file got created fine in both cases but the stacks don't get captured on kernel 4.14. What am I missing?

Here are some details:

# perf --version
perf version 4.14.313-235.533.amzn2.aarch64

# perf record -C0 -g -e armv8_pmuv3_0/event=0x11,name=cycles/ -- sleep 60

# ls -larth perf.data
-rw------- 1 root root  53M Jun 23 15:30 perf.data

# perf script > k4_script_cycles.out

# less k4_script_cycles.out
perf 14536 [000] 162764.224500: cycles: 
[ empty]

[ empty]
perf 14536 [000] 162764.224523: cycles: 

Thank you.

AshinZ commented 1 year ago

Maybe you can try to do profile without "-C0" to check this is a system problem or a use problem.