[bootlin/training-materials updates] master: labs/sysdev-application-development-and-debugging: add "perf record" for system wide analysis (9b633f3c)

[Michael Opdenacker]

Repository : https://github.com/bootlin/training-materials
On branch  : master
Link       : https://github.com/bootlin/training-materials/commit/9b633f3cf8e3286f398726f24ed78d2843c49e00

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commit 9b633f3cf8e3286f398726f24ed78d2843c49e00
Author: Michael Opdenacker <michael.opdenacker at bootlin.com>
Date:   Mon Oct 24 09:41:53 2022 +0200

    labs/sysdev-application-development-and-debugging: add "perf record" for system wide analysis
    
    Signed-off-by: Michael Opdenacker <michael.opdenacker at bootlin.com>


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9b633f3cf8e3286f398726f24ed78d2843c49e00
 .../sysdev-application-development-and-debugging.tex                  | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/labs/sysdev-application-development-and-debugging/sysdev-application-development-and-debugging.tex b/labs/sysdev-application-development-and-debugging/sysdev-application-development-and-debugging.tex
index 7e88453e..f90cf4c8 100644
--- a/labs/sysdev-application-development-and-debugging/sysdev-application-development-and-debugging.tex
+++ b/labs/sysdev-application-development-and-debugging/sysdev-application-development-and-debugging.tex
@@ -404,6 +404,10 @@ currently playing audio. Then SSH to your board and run \code{perf top}
 (working better through SSH) to see live information about kernel and
 userspace functions consuming most CPU time.
 
+This is interactive, but hard to analyze. You can also run \code{perf
+record} for about 30 seconds, followed by \code{perf report} to have
+a useful summary of system wide activity for a substantial amount of time.
+
 This was a very brief start at practising with \code{perf}, which offers
 many more possibilities than we could see here.