Re: KDevelop using 100% of CPU all the time

On Mittwoch, 19. Juli 2017 19:23:50 CEST Benjamin CAILLAT wrote:
> Hello,
> 
> KDevelop (5.1.1) on my Ubuntu (14.04.5 64 bits) is using 100% of one of my
> core all the time. The project I'm working on is pretty big so it takes a
> bit of time to load / parse everything, which is understandable. However,
> KDevelop keeps using all the CPU even when the parsing is done (no task
> window in the bottom right corner). Even after several hours, it keeps
> using 100% of the CPU.
> 
> After attaching strace, I can see that it apparently loops on a poll:
> poll([{fd=33, events=POLLIN}, {fd=23, events=POLLIN}, {fd=36,
> events=POLLIN}, {fd=55, events=POLLIN}, {fd=11, events=POLLIN}, {fd=28,
> events=POLLIN}, {fd=7, events=POLLIN}], 7, 0) = 0 (Timeout)
> poll([{fd=33, events=POLLIN}, {fd=23, events=POLLIN}, {fd=36,
> events=POLLIN}, {fd=55, events=POLLIN}, {fd=11, events=POLLIN}, {fd=28,
> events=POLLIN}, {fd=7, events=POLLIN}], 7, 0) = 0 (Timeout)
> poll([{fd=33, events=POLLIN}, {fd=23, events=POLLIN}, {fd=36,
> events=POLLIN}, {fd=55, events=POLLIN}, {fd=11, events=POLLIN}, {fd=28,
> events=POLLIN}, {fd=7, events=POLLIN}], 7, 0) = 0 (Timeout)
> 
> Has anyone experienced the same issue / has an idea about how to fix that?

Never seen this, please use a profiler like perf to figure out what is going 
on here.

kdevelop
# wait for it to "settle"
perf record --call-graph dwarf --pid $(pidof kdevelop)
# after ~5s or so interrupt
^C

Then use hotspot of FlameGraph to analyze the data, or look at `perf report` 
directly.

Bye

-- 
Milian Wolff
[email protected]
http://milianw.de

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