Profile system - no debug symbol and no binary name in hotspot (perf)

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1

I’m trying to compare X11 and wayland performance - Wayland seems to waste resources way more (100% single core utilization) over moving the mouse.

I’ve recorded the performance in Hotspot (it uses perf under the hood), and I’ve configured the symbol server to be

https://debuginfod.opensuse.org

I’ve also modified /proc/sys/kernel/perf_event_paranoid to -1, to enable profiling the system.

But the main process which consumes more than 98% or the CPU does not have a binary name, nor a symbol associated with it.

Here’s the recorded profile (DWARF): https://file.io/0e2wKGxVbZEm

Any ideas on how I can see what binary and what function consume the resources?

2

recorded profile for the Wayland profiling: https://file.io/d13kuuSiG4fT
This one is even worse - everything is unidentified…

In this one kwin_wayland takes 25% cpu (a single core at 100%), as opposed to the one taken in X11, where nothing consumed much of the CPU.

3

Just install relevant debug packages manually.

4

Thanks for the reply.

After your suggestion I’ve installed many plasma6, kf6*, kwin, qt6, libstdc++, glibc, dri3 etc. debuginfo… I still get only ?? for binary and for symbols in my profiling data…

Maybe this message has something to do with it?
Failed to parse kernel symbol mapping file “//proc/kallsyms”: Mapping is empty.

There are also other lines such as
Could not find ELF file for anon_inode:i915.gem. This can break stack unwinding and lead to missing symbols.

or

Could not find ELF file for /home/or/.cache/plasmashell/qmlcache/27ccb62863115205a0af1c213216db42ae58ba6c.qmlc (deleted). This can break stack unwinding and lead to missing symbols.

5

I’ve also found that modifying
/proc/sys/kernel/kptr_restrict
to 0 enables many symbols, but still the top most cycles consuming process is marked as ?? as well as its function calls… I have no idea how to proceed.