From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A30F321FF33 for ; Fri, 5 Sep 2025 16:07:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757088463; cv=none; b=IlBR+SxzDlTZUPYrRYrjGxXgBt7DYLplTnsg+4BMRGUDkS+vXAJ5Ndd8DdSvgh97P/ABoG4O52TaSDboDMVZ8ehyj20DYKe8Ox5Z7mKpG1KUtoDNseM0SG8T4bOh+wQZ9wpiaq8tkOGcjTt8+d9K833uAcavG4CLM5JdcwF+B8A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757088463; c=relaxed/simple; bh=WECVg+IYJGbdMp4S7vwLHgSbY7woQhqjoQF/7T9F2Iw=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=kpjmA97P7aLdrEufcmaoDymTW9jNA3bH2DPN0l23d9obKq+itAgjKMG9JggiiOXe9+zzea0RMt2bUEKQ8rphJL3TLJqCFo6nvhtgIjO+08uB7Tf9ihuG+ZPlcf6y8nHsIFkuJpZmqbvZEMASuh3+E7JHQb9Gi1ZYbR1AR4xUx04= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=JQyMnj/s; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=U0OhuL0l; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="JQyMnj/s"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="U0OhuL0l" From: John Ogness DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1757088458; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=w70u4cgFzxEBXT3sf3NwfOJfES+PMdtL03PKnbJzbXo=; b=JQyMnj/s5XJxvyS3zkvJjVsoVPZpuXjWjhK1s5wi3p5M3Cc1c06DsH3cf6Up6Tw6eo0aQh dUrmnaZtKiHRuGzTT5/r7JkQQ+NYA9+6OdINZ5FBWWUfb/Fjt/ehthWENCf1f8MoC9uqqz A6kuc5LDYHCrTF41Jxt9r5x3C5fh300jGrgQmz4GUmBSFLOOzyrh+W3In76P5Y0LZp6s1C uQWqonSmV9iJDAH1zbRWxRyqBMuZ0RsKvySthN1NkUreuaReJQOTCwE1Y/GzugB20zkDOi RCxrRAXwtIIpzN6UGcm04LLmRFWsqeKKOsl/hJP+9Zb24BTVBE1InxlQK5Conw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1757088458; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=w70u4cgFzxEBXT3sf3NwfOJfES+PMdtL03PKnbJzbXo=; b=U0OhuL0l/+BZgfsItrexVD0V85PPKOOSfHm30H8jVYG4TNHsLSqFNb+t/P0IvDL7T0vUG7 5Z2Q8TbWp5DggsBg== To: Marc Gonzalez , Daniel Wagner Cc: linux-rt-users@vger.kernel.org, Steven Rostedt , Thomas Gleixner , Sebastian Andrzej Siewior , Daniel Wagner , Clark Williams , Pavel Machek , Luis Goncalves , John McCalpin Subject: Re: Large(ish) variance induced by SCHED_FIFO In-Reply-To: <42c5fb53-d423-41a5-80d9-557ff2a3e804@free.fr> References: <5f7496eb-bf62-4cc9-bef0-9cae97a93dca@free.fr> <841polf13z.fsf@jogness.linutronix.de> <42c5fb53-d423-41a5-80d9-557ff2a3e804@free.fr> Date: Fri, 05 Sep 2025 18:13:37 +0206 Message-ID: <84ldmsevcm.fsf@jogness.linutronix.de> Precedence: bulk X-Mailing-List: linux-rt-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain On 2025-09-05, Marc Gonzalez wrote: >>> (I used CLOCK_MONOTONIC_RAW.) >> >> Not really relevant to your issue, but you should always use CLOCK_MONOTONIC. > > Could you provide some insight as to why CLOCK_MONOTONIC is > preferable? CLOCK_MONOTONIC is tracking in time units as defined by humans. CLOCK_MONOTONIC_RAW is tracking in time units defined by some hardware. John