Hi, Kurt, May I know whether you used "root" user to run stress-ng? using "root" user will change the scheduler to be "SCHED_RR", so would you please share test result with root and non-root users? Thanks. Best Regards, Jiafei. -----Original Message----- From: linux-rt-users-owner@xxxxxxxxxxxxxxx <linux-rt-users-owner@xxxxxxxxxxxxxxx> On Behalf Of Kurt Kanzenbach Sent: Wednesday, June 10, 2020 1:58 PM To: Vladimir Oltean <olteanv@xxxxxxxxx> Cc: linux-rt-users@xxxxxxxxxxxxxxx; lkml <linux-kernel@xxxxxxxxxxxxxxx>; rcu@xxxxxxxxxxxxxxx; Colin King <colin.king@xxxxxxxxxxxxx> Subject: [EXT] Re: stress-ng --hrtimers hangs system Hi Vladimir, On Tue Jun 09 2020, Vladimir Oltean wrote: > Just out of curiosity, what and how many CPU cores does your ARM64 box > have, and what frequency are you running them at? > Mine is a dual-core A72 machine running at 1500 MHz. That particular machine has a dual core Cortex A53 running at 1GHz. Thanks, Kurt