Hi Ahmed, thanks for the answer! Do you know if it would be valid for GTK interface applications? Michel Em qui., 11 de mar. de 2021 às 09:58, Ahmed S. Darwish <a.darwish@xxxxxxxxxxxxx> escreveu: > > On Wed, Mar 10, 2021 at 05:07:47PM -0300, Michel Macena Oliveira wrote: > > > > I'm currently developing a time benchmark application where I want > > to measure a real time thread latency. My application is based on > > Cyclictest from > > the rt-tests suit. > ... > > > > I programmed in such way that it would be equivalent to Cyclict test > > > ... > > > > At least that's what I expected, but my latencies are much bigger than > > Cyclictest ones. > > > > I don't know the nature of the "time benchmark" application you are > writing. > > Just a small hint that if you're doing any heavy OpenGL graphics within > that application, the latency can shoot up significantly. On some of our > Intel boxes, this can lead to an increase of 100-200 microseconds. > > That's because since Intel Gen9+ GPUs, Intel shares the Last-Level Cache > (and thus also memory bandwidth) between the GPU and the CPU. This > benefits graphical applications, but hurts predicatbility significantly. > > Good luck, > > -- > Ahmed S. Darwish > Linutronix GmbH
