From a3a82efbf6b5b3af840c70038b1b599ba29003ac Mon Sep 17 00:00:00 2001 From: Rouven Czerwinski Date: Fri, 13 May 2022 20:30:19 +0200 Subject: realtime: request SCHED_RR using CAP_SYS_NICE Try to gain SCHED_RR (round-robin) realtime scheduling privileges before starting the server. This requires CAP_SYS_NICE on Linux systems. We additionally register a pthread_atfork callback which resets the scheduling class back to SCHED_OTHER (the Linux system default). Due to CAP_SYS_NICE, setting RLIMIT_RTPRIO has no effect on the process as documented within man 7 sched (from Linux): Privileged (CAP_SYS_NICE) threads ignore the RLIMIT_RTPRIO limit; as with older kernels, they can make arbitrary changes to scheduling policy and priority. See getrlimit(2) for further information on RLIMIT_RTPRIO Note that this requires the sway distribution packagers to set the CAP_SYS_NICE capability on the sway binary. Supersedes #6992 --- include/sway/server.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/sway') diff --git a/include/sway/server.h b/include/sway/server.h index d8ccd64f..3d59ca56 100644 --- a/include/sway/server.h +++ b/include/sway/server.h @@ -173,4 +173,6 @@ void handle_pointer_constraint(struct wl_listener *listener, void *data); void xdg_activation_v1_handle_request_activate(struct wl_listener *listener, void *data); +void set_rr_scheduling(void); + #endif -- cgit v1.2.3