From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BA1CEC3A589 for ; Thu, 15 Aug 2019 13:31:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8F8E6208C2 for ; Thu, 15 Aug 2019 13:31:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="k8U2CVQd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732277AbfHONbD (ORCPT ); Thu, 15 Aug 2019 09:31:03 -0400 Received: from mail-wr1-f68.google.com ([209.85.221.68]:43388 "EHLO mail-wr1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730304AbfHONbC (ORCPT ); Thu, 15 Aug 2019 09:31:02 -0400 Received: by mail-wr1-f68.google.com with SMTP id y8so2207260wrn.10 for ; Thu, 15 Aug 2019 06:31:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=3Gc24i+ADeGl5GmPmYJ2P+bDpzGS14YvtsEHbL9psAE=; b=k8U2CVQdvkA9300Ez6JjKUnzI0DwiNhEf7yvZMj1ShE3fjTxaafj/0UCam7z584TKu IpRc88E+vf9GeOxtvjqRN5siL7Us7x5aKWwa6adJJdH/nJFo8g/gesLdBfr9XE+wDCY/ e0KgF8Me6Hl7ziQQM+F0jjIoAF6pZEhCbyVrpwpZmviWitTy7XJ/BDvbbn8pS/Yfc2X6 P7fSOTlWAAOt3+szt6OTwFNO430gj5bLmQ4b5/YLTN/sl3q+PkmFYvTPJYqL8nrAvr/9 E9A5qM31rNEt0vhoUOWjT46ZBxjtRlhYe4LWSC1IS2w/hAJ45PzIpXij8FULHIXYmOL/ PBkQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=3Gc24i+ADeGl5GmPmYJ2P+bDpzGS14YvtsEHbL9psAE=; b=px4omvwN9rndUhMBBatbiqXYAqDi/kpuhakgcoarjPECeASl0J5XkKN/n6d+mhZmUA RXUTJerCc5xn80FtKSoeXghZ0x5n7PSfRUpvxEv9rYbLD76hdqz6mR/UYgvFRkiSDotq /BNhB2ZMRz8G4gupZPgfevN/XUU0uRJtB5DKBcqD3gkgWPrtdNB8T9gvzsc+xdaUh7Dj KepUjaNZtjCkH5TsFpSPRdcbM7xtmRLjkM7YK95EgkWIqMMgSbK8HEdGEDqHGRUQDfwf H+zuC2mU9V+U+1Fod7HdwzNF2tnR04FEtUL3UK40fnkl36SLchTzeIRVjeQUdfiCYvr3 u9AQ== X-Gm-Message-State: APjAAAWgt9piV1CVbQUYKKCXt4Ouuu/scPsj/zzh2q0+BLWBDqRLONKi XCis+Nbw0fBDqKvRNxqZDksaYI9F8LBapyhZkls= X-Google-Smtp-Source: APXvYqxc9kYTKP8B/mOtDPxkj5RRMoL/a3DAtX0XnWcWdIO8S2yeLd4eP686n60nQyt/I9mMU+Li/iE3t92NC65cZtU= X-Received: by 2002:a5d:4bc1:: with SMTP id l1mr5664033wrt.259.1565875860490; Thu, 15 Aug 2019 06:31:00 -0700 (PDT) MIME-Version: 1.0 References: <20190813095306.xqgq3uusdpj7dhy7@linutronix.de> <20190814112656.z3de2rgbqzpaquz5@linutronix.de> <20190815082955.olo3phbqj6disk3q@linutronix.de> <87a7ca4nh6.fsf@linutronix.de> In-Reply-To: <87a7ca4nh6.fsf@linutronix.de> From: Paul Thomas Date: Thu, 15 Aug 2019 09:30:48 -0400 Message-ID: Subject: Re: poor cyclictest results with 5.0 series rt for arm64 To: John Ogness Cc: Sebastian Andrzej Siewior , Thomas Gleixner , linux-rt-users , dunc.mcphie@gmail.com, Anders Roxell Content-Type: text/plain; charset="UTF-8" Sender: linux-rt-users-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rt-users@vger.kernel.org > Where in this trace is there a latency spike? I could not see one. Hi John, For the 5.2.0-rt1 trace data set I believe the latency is with cyclicte-1935 at the end. If I just look at the "cyclicte-1935 ... finish_task_switch <-__schedule" lines then the delta-t's are mostly around 200us except for the last delta-t which is >5000us cyclicte-1935 1d...3.. 84243668us : uao_thread_switch <-__switch_to cyclicte-1935 1d...3.. 84249436us : finish_task_switch <-__schedule The actual cyclictest output is shown below: # ./cyclictest -S -m -n -p 99 -i 200 -h 700 -f -b 5000 # /dev/cpu_dma_latency set to 0us INFO: debugfs mountpoint: /sys/kernel/debug/tracing/ policy: fifo: loadavg: 5.55 1.84 0.66 11/136 1941 T: 0 ( 1934) P:99 I:200 C: 411188 Min: 30 Act: 30 Avg: 93 Max: 652 T: 1 ( 1935) P:99 I:200 C: 382925 Min: 47 Act: 5713 Avg: 123 Max: 5713 T: 2 ( 1936) P:99 I:200 C: 395011 Min: 40 Act: 40 Avg: 117 Max: 561 T: 3 ( 1937) P:99 I:200 C: 392379 Min: 36 Act: 36 Avg: 109 Max: 636 thanks, Paul