From nobody Fri Nov 18 04:47:58 2022 X-Original-To: freebsd-current@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4ND46L50DJz4hJR5 for ; Fri, 18 Nov 2022 04:48:10 +0000 (UTC) (envelope-from hps@selasky.org) Received: from mail.turbocat.net (turbocat.net [88.99.82.50]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4ND46J6nQbz4DZq for ; Fri, 18 Nov 2022 04:48:08 +0000 (UTC) (envelope-from hps@selasky.org) Authentication-Results: mx1.freebsd.org; dkim=none; spf=pass (mx1.freebsd.org: domain of hps@selasky.org designates 88.99.82.50 as permitted sender) smtp.mailfrom=hps@selasky.org; dmarc=none Received: from [10.36.2.69] (unknown [84.210.222.10]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mail.turbocat.net (Postfix) with ESMTPSA id 087DA2600C9 for ; Fri, 18 Nov 2022 05:48:00 +0100 (CET) Message-ID: <7ad10a5e-29d6-aaef-25cf-407d65f056cc@selasky.org> Date: Fri, 18 Nov 2022 05:47:58 +0100 List-Id: Discussions about the use of FreeBSD-current List-Archive: https://lists.freebsd.org/archives/freebsd-current List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-current@freebsd.org MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:102.0) Gecko/20100101 Thunderbird/102.4.1 Content-Language: en-US To: FreeBSD Current From: Hans Petter Selasky Subject: ULE realtime scheduler advice needed Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spamd-Result: default: False [-3.29 / 15.00]; NEURAL_HAM_LONG(-1.00)[-1.000]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; NEURAL_HAM_SHORT(-0.99)[-0.989]; R_SPF_ALLOW(-0.20)[+a:mail.turbocat.net]; MIME_GOOD(-0.10)[text/plain]; PREVIOUSLY_DELIVERED(0.00)[freebsd-current@freebsd.org]; DMARC_NA(0.00)[selasky.org]; RCPT_COUNT_ONE(0.00)[1]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MLMMJ_DEST(0.00)[freebsd-current@freebsd.org]; FROM_HAS_DN(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; ARC_NA(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; TO_DN_ALL(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; R_DKIM_NA(0.00)[]; ASN(0.00)[asn:24940, ipnet:88.99.0.0/16, country:DE]; MIME_TRACE(0.00)[0:+]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_TLS_ALL(0.00)[] X-Rspamd-Queue-Id: 4ND46J6nQbz4DZq X-Spamd-Bar: --- X-ThisMailContainsUnwantedMimeParts: N 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? --HPS