not further backend_bound output in the toplev -l2 about pmu-tools HOT 4 CLOSED

another question ,maybe not related with pmt-tools.
How can we know whether the app performance is cpu bound,so we can use the topplev?

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I don't understand the first question.
--metrics contains a CPU usage metric. I moved it into the basic model.
However it is hard to say in general because it depends on the number of cores you intend to use, and the numbre of other processes running.

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let me explain the first question,
1,
first run :toplev.py sleep 60

Using level 1.
perf stat -x, -e '{cpu/event=0x3c,umask=0x0,any=1/,cpu/event=0xe,umask=0x1/,cpu/event=0x9c,umask=0x1/,cpu/event=0xd,umask=0x3,cmask=1,any=1/,cpu/event=0xc2,umask=0x2/}' -A -a sleep 60
S0-C0 FE Frontend_Bound: 35.21%
S0-C0 BE Backend_Bound: 50.81% //maybe the bound.
S0-C1 FE Frontend_Bound: 34.63%
S0-C1 BE Backend_Bound: 43.94%
.....
second run: toplev.py -l2 sleep 60
S0-C0 FE Frontend_Bound: 32.92%

S0-C0 FE Frontend_Bound.Frontend_Latency: 27.60%

S0-C0 BE Backend_Bound: 52.92%

S0-C1 FE Frontend_Bound: 36.04%
S0-C1 FE Frontend_Bound.Frontend_Latency: 29.17%
......
S0-C0-T1BE/Mem Backend_Bound.Memory_Bound: 0.00% mismeasured

2,
if normal,when i carry the second run,the command output should have the level 2 result,such as 'S0-C0 FE Frontend_Bound.Frontend_Latency: 27.60%'

as for the S0-C0 BE Backend_Bound,in the first run,we can see it domain 50.81%,so maybe in the second run,we should also see the detail of the S0-C0 BE Backend_Bound. am i right?

but you look,we cannot found the S0-C0 BE 's subitems,such as 'S0-C0 BE Backend_Bound.*'.
so we cannot see the details about the S0-C0 BE Backend_Bound.
my kernel is ubuntu 3.16.0-31-generic.

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The second run is multiplexing, so the results can differ. See
https://github.com/andikleen/pmu-tools/wiki/reasons-for-toplev-measuring-issues

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