TIL: using hpet (instead of tsc) as #Linux clocksource apparently can cause massive slowdowns in some workloads. E.g. when reading data from a socket using select() and read(), with hpet clock the select() calls alone can reduce throughput down to 25%. #Perf profiling shows that the kernel spends lots of time in read_hpet().

Guess now I cannot postpone debugging the clock drift problems that occur with tsc clocksource on this one system :-(

#performance #softwareDevelopment #HPET #TSC #clocks

Hotspot: Linux `perf` GUI for performance analysis

https://github.com/KDAB/hotspot

#HackerNews #Hotspot #Linux #perf #GUI #performance #analysis #KDAB #GitHub

Can anybody provide me with a reason why #Ubuntu packaged #Linux #perf doesn't/ shouldn't ship a tips.txt file? If you run perf without manually installing the tips.txt it will complain and ask you to install perf (see very bottom of the screen: `Cannot load tips.txt file, please install perf!`).

It seems to me that shipping the 5.4KiB file in the package would be helpful.

 I wanted to try 🔥 📈 flamegraph (perf) today, so I wrote a quick program to iterate over some "stuff" ™️ .

Then I wanted to see some function calls so I added more functionality.

Then I duplicated it to iterate over some other "stuff" ™️ .

Then I added some nice things to alter the output.

Then i thought, "ah I'll snap it".

⏲️ A 5 minute test turned into a few hours and now I have two nice programs which I've wanted for a while, and a Snap.

I do it to myself 🙄

🌐 Perf: https://github.com/torvalds/linux/blob/master/tools/perf
🌐 https://perfwiki.github.io/main/
🌐Flamegraph: https://github.com/flamegraph-rs/flamegraph?tab=readme-ov-file#flamegraphs-are-the-beginning-not-the-end

#Flamegraph #Perf #Linux #Snapcraft #Snap #Experiment #Programming #Rust #RabbitHoles #Ubuntu

Today's bug is a `perf` hangup bug: https://lkml.org/lkml/2025/5/5/1089

There a simple `perf record -a` / `perf report` hangs up if you happen to have a `/dev/dri/renderD128` file `mmap()`ed in any of the processes. Browsers and compositors usually do have them `mmap()`ed.

#perf #bug

How we ended up rewriting NuGet Restore in .NET 9 - .NET Blog

https://devblogs.microsoft.com/dotnet/rewriting-nuget-restore-in-dotnet-9/

#dotnet #nuget #perf

"Le Grand Atelier", première. Journée
portes ouvertes des Ateliers de la ville
de Fribourg. Samedi 3 mai 10h-17h. Avec un programme alléchant concocté par l'excellent David Bruhlart.

#artiste #atelier #fribourg #openaccess #perf

https://www.grandatelier.ch/