Date: Tue, 22 Nov 2022 22:38:04 +0100 From: Hans Petter Selasky <hps@selasky.org> To: mike tancsa <mike@sentex.net>, FreeBSD Current <freebsd-current@freebsd.org> Subject: Re: ULE realtime scheduler advice needed Message-ID: <1a404155-4ca9-4e88-4c40-5407c2ae52a9@selasky.org> In-Reply-To: <8d8c4b03-323a-8e4d-44fd-e47749d2fd85@sentex.net> References: <7ad10a5e-29d6-aaef-25cf-407d65f056cc@selasky.org> <8d8c4b03-323a-8e4d-44fd-e47749d2fd85@sentex.net>
next in thread | previous in thread | raw e-mail | index | archive | help
On 11/22/22 20:28, mike tancsa wrote: > On 11/17/2022 11:47 PM, Hans Petter Selasky wrote: >> Hi, >> >> I'm doing some work with audio and have noticed some problems with the >> ULE scheduler. I have a program that generate audio based on >> key-presses. When no keys are pressed, the load is near 0%, but as >> soon as you start pressing keys, the load goes maybe to 80% of a CPU >> core. This program I run with rtprio 8 xxx. The issue I observe or >> hear actually, is that it takes too long until the scheduler grasps >> that this program needs it's own CPU core and stops time-sharing the >> program. When I however use cpuset -l xxx rtprio 8 yyy everything is >> good, and the program outputs realtime audio in-time. >> >> Or is this perhaps a CPU frequency stepping issue? >> >> Any advice on where to look? >> > A long shot, but I am curious if by chance you have hwpstate_intel for > your cpu frequency driver. If so, does setting > dev.hwpstate_intel.0.epp=0 make any difference ? > Yes, I have four of those, set to 50 by default. Let me try. --HPS
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?1a404155-4ca9-4e88-4c40-5407c2ae52a9>