From nobody Tue Nov 22 21:38:04 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 4NGyL10PcZz4hgNl for ; Tue, 22 Nov 2022 21:38:17 +0000 (UTC) (envelope-from hps@selasky.org) Received: from mail.turbocat.net (turbocat.net [IPv6:2a01:4f8:c17:6c4b::2]) (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 4NGyL05B1Nz4CdN for ; Tue, 22 Nov 2022 21:38:16 +0000 (UTC) (envelope-from hps@selasky.org) Authentication-Results: mx1.freebsd.org; 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 4F9FA26016E; Tue, 22 Nov 2022 22:38:07 +0100 (CET) Message-ID: <1a404155-4ca9-4e88-4c40-5407c2ae52a9@selasky.org> Date: Tue, 22 Nov 2022 22:38:04 +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 Subject: Re: ULE realtime scheduler advice needed To: mike tancsa , FreeBSD Current References: <7ad10a5e-29d6-aaef-25cf-407d65f056cc@selasky.org> <8d8c4b03-323a-8e4d-44fd-e47749d2fd85@sentex.net> Content-Language: en-US From: Hans Petter Selasky In-Reply-To: <8d8c4b03-323a-8e4d-44fd-e47749d2fd85@sentex.net> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 4NGyL05B1Nz4CdN X-Spamd-Bar: ---- X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; ASN(0.00)[asn:24940, ipnet:2a01:4f8::/32, country:DE] X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-ThisMailContainsUnwantedMimeParts: N 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