
Taskbar Latency and Kernel Calls - nikbackm
https://randomascii.wordpress.com/2019/09/08/taskbar-latency-and-kernel-calls/
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tanseydavid
I really appreciate your efforts on this.

I am fairly certain that I experience the same latency issue with right-click
context menus in Windows Explorer as what you have described.

I was hopeful that the recent acquisition of a new machine with a fresh WIN10
install on it would provide me relief from this issue -- but the situation is
unchanged with the fresh install.

Your research shows me that the underlying situation and cause is hardly
something that "I am imaging" \-- this is an ugly piece of mis-performant
code.

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brucedawson
Note that my blog post now lists two solutions that users can implement. Check
them out. They make a big difference.

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nisa
Any idea how to do something similiar on Linux? I'm using Plasma 5 on Arch
Linux and from time to time I'm seeing mysterious hangs (seconds to minutes)
on the Plasma UI - CPU profiling is probably useless and for me it looks like
perf record is just way to broad and the hangs are not due to CPU churning but
probably something else (scheduler or locks - I have no idea), I'm not a dev
but it would be nice to be able to at least produce a proper bug report and
searching the root cause.

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pelagius
Depending on your CPU, you might be able to use SATT:
[https://github.com/intel/satt](https://github.com/intel/satt)

~~~
nisa
This looks great! Thanks for the hint!

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tinus_hn
Too bad Microsoft is too busy with integrating ‘telemetry’ spyware and
parading their ‘wasting your resources isn’t our problem’ mindset to fix these
obvious issues that have been part of the Windows experience for decades now.

~~~
brucedawson
Ironically I suspect it is the lack of telemetry for this action that allowed
this performance problem to linger this long. If Microsoft had this action
Perftrack instrumented and had their usual 100 ms performance target then they
could grab ETW traces from the field and would have figured this out.

Instead they appear to have been dependent on anecdotal evidence and nobody
taking responsibility.

Or maybe I'm wrong. Maybe this action was instrumented but was then ignored.
That would be sad.

Perftrack reference: [https://channel9.msdn.com/Blogs/Charles/Inside-
Windows-7-Rel...](https://channel9.msdn.com/Blogs/Charles/Inside-
Windows-7-Reliability-Performance-and-PerfTrack)

~~~
tinus_hn
If they’re missing basic problems like this the solution is not more
telemetry, the solution is qa. Not even better qa, just start with basic qa.
Because right now they’re just doing nothing and treating their paying
customers as alpha testers. I don’t quite understand why people accept it.

~~~
brucedawson
Some of the slowdown should have been noticed by QA. But most of this slowdown
occurs when you have used your machine for long enough to accumulate 4 MB of
File Explorer history. Telemetry is the perfect tool for catching this sort of
real in-the-field problem. More QA is also important.

