From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ej1-f52.google.com (mail-ej1-f52.google.com [209.85.218.52]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 457EBA23 for ; Thu, 13 Jun 2024 16:09:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.218.52 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718294962; cv=none; b=jKtpGLXWWYYACW3y6rbfqp+N8QAw2zxli9zNE1uvEsZLENikIue9o1px7JOEYFhmuVtL4wixIIp91F/XMHTV14bdHOIeV5agqrboBskgyQqRA+kAMUTr2MnRthKd0N8hPpeVanh3fqGEDzVmsZj0skH2gdekJnSu1io7eKvhL44= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718294962; c=relaxed/simple; bh=1XlG3CR0xpDqPqMh87D+GrDZX5VejYOXn1Sz5BA+hVk=; h=References:From:To:Cc:Subject:Date:In-reply-to:Message-ID: MIME-Version:Content-Type; b=ZLk7URXL1L83knQFv3XixULEedFpPbLAimjeZ3wk58wB4XBdw6tlF+HrqGipwv7BrnBBE/4W3d+Q4ywnxlI8n/9xNkFw5zxkZN0cN2/SFfVlaZ7LfFpWFq1r8AVW05+n3Ppxm5rHkoYAKOYv88K8Hvx7AeY5LxYiiRdp5JoHAIk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=xenomai.org; spf=pass smtp.mailfrom=gmail.com; arc=none smtp.client-ip=209.85.218.52 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=xenomai.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-ej1-f52.google.com with SMTP id a640c23a62f3a-a6e349c0f2bso177397266b.2 for ; Thu, 13 Jun 2024 09:09:19 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1718294958; x=1718899758; h=mime-version:message-id:in-reply-to:date:subject:cc:to:from :user-agent:references:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=vXWpTvblqs5qlMfWhv7cMBMgUihwxO9lxFVhCz5Ndlk=; b=ChHoS7IGxzWzA+1jWkLIJL2RYle1XZHTxyhtvyz/b6Tti/0+gw0aF7A/PpIayXuJfD Zt873qBwn2DHqPkLkbN1bv0vi8xqCCnfgWTZQV6vWI1f0x0hqFv9IdPihGIE01eaoDVE 6+mcN/Vk3vFDxWD6WRH5sNi5EUv2j+pUAEmSwSr0lnkq/58giwTbdiKml27Xv154YgW9 awTX48/QEF6u4gS3SQZsrqbDWfOEI5Xug8tochNHpAnh+186SwxFLTgfOmglLh2n5uUi VDqwsvICRfRYO9xYFEW/UYhwkmNHIVECWKJEsGOHXX8ahcotGIVYcy3vGK3As9aHXGjt 9d3g== X-Forwarded-Encrypted: i=1; AJvYcCWG4zkk6keZqZUeo/aXb5ZjNCAklcyeFkydhHGWOMQIqEKfDN0FcCt8A5v1kk5p3i53HUMq75s+7NfAuvLtK3VFU5WfcGjBpw== X-Gm-Message-State: AOJu0YxZyX/a6uLxbdPFzdROcM5JCSSzxJUjSwv+UMEYA5Q01YEsW9OO XuqNHx1QCVBMIpWg0ZXJfWAtmYsShHk6eoTLyDW8l2dy7mn4zRenqlCLiA== X-Google-Smtp-Source: AGHT+IGxhMeb16meifDx7j7T6fDh4MS2aBiS3r5Wd3jkrSS7E96ENbAhGSmG/KvUNovC9mqjtkKlkQ== X-Received: by 2002:a17:906:57c2:b0:a6f:eb8:801a with SMTP id a640c23a62f3a-a6f60dc51c7mr12125966b.56.1718294958076; Thu, 13 Jun 2024 09:09:18 -0700 (PDT) Received: from pyro ([2a01:e0a:19b:3cd0:989a:5c4b:b7ff:baf]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a6f57552633sm83467066b.191.2024.06.13.09.09.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 13 Jun 2024 09:09:17 -0700 (PDT) References: <20240613134557.4013044-1-tobias.schaffner@siemens.com> <20240613134557.4013044-2-tobias.schaffner@siemens.com> <87frtgrker.fsf@xenomai.org> User-agent: mu4e 1.10.5; emacs 29.3 From: Philippe Gerum To: Jan Kiszka Cc: Tobias Schaffner , xenomai@lists.linux.dev Subject: Re: [libevl][PATCH 1/4] Copy dohell from Xenomai 3 Date: Thu, 13 Jun 2024 17:55:02 +0200 In-reply-to: Message-ID: <877cesrfir.fsf@xenomai.org> Precedence: bulk X-Mailing-List: xenomai@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain Jan Kiszka writes: > On 13.06.24 16:23, Philippe Gerum wrote: >> >> Tobias Schaffner writes: >> >>> Dohell is used as the default load generator in Xenomai 3. Add it to >>> libevl to be able to stress the system while testing evl. >>> >> >> dohell is obsolete. Let's move to stress-ng or something alike for x4. >> > > See my comment on patch 3: If you can name a configuration of stress-ng > that stresses a co-kernel more than what dohell does, we can take it. > Otherwise, I would strongly recommend to not do less hell over here. > The most important stress dohell applies is basically hackbench and a dd loop trashing the D-cache. The latter can be obtained with a combo of VM+I/O tests from stress-ng. So basically, the whole issue boils down to having hackbench on board, provided we cannot generate the same load profile with stress-ng with a CPU bound stressor. Besides, I never saw any added value in running ltp tests compared to a combo of stress-ng stressors when it comes to latency testing. We obviously don't want to throw less hell, but throwing more obsolete stuff is not an option either. So that's a NAK for v4 ATM, I'll gather more information about how we could leverage stress-ng in order to compare to dohell. This is worth a shot. -- Philippe.