Linux 6.19 does bring some nice performance improvements overall but during my early testing there were some regressions and I ended up bisecting some of them to the scheduler changes in Linux 6.19 .
Intel's Kernel Test Robot did also report a scheduler regression with Schbench using a Phoronix benchmark run:
"kernel test robot noticed a 52.4% regression of pts.schbench.32.usec,_99.9th_latency_percentile"
That regression was spotted on this scheduler commit .
Queued a few days ago into the tip/tip.git's sched/core branch is sched/fair: Fix sched_avg fold to fix that reported 52.4% regression:
"After the robot reported a regression wrt commit: 089d84203ad4 ("sched/fair: Fold the sched_avg update"), Shrikanth noted that two spots missed a factor se_weight()."
That patch will presumably be sent in soon for the ongoing Linux 6.19 cycle.