From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by sourceware.org (Postfix) with ESMTPS id C91B438930DE for ; Mon, 26 Apr 2021 19:13:47 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org C91B438930DE IronPort-SDR: P9tYgMRPmKp20ygIdYvhmPbD3ljxNtccFax0DnGmr2QDsul/40ih3nDD+1vOcg9egCafx20bVI XbeiwI0f6vkA== X-IronPort-AV: E=McAfee;i="6200,9189,9966"; a="196451750" X-IronPort-AV: E=Sophos;i="5.82,252,1613462400"; d="scan'208";a="196451750" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Apr 2021 12:13:46 -0700 IronPort-SDR: MFLL8LoLxlKYUUFx8TnM/uOol46ATfkBZWNA5s3bk9ZXMeeQEt6sTThngtLz1D9iCy2bLmD2AN wz8RgSKIAdXQ== X-IronPort-AV: E=Sophos;i="5.82,252,1613462400"; d="scan'208";a="429507803" Received: from tassilo.jf.intel.com ([10.54.74.11]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Apr 2021 12:13:46 -0700 Date: Mon, 26 Apr 2021 12:13:45 -0700 From: Andi Kleen To: Hongtao Yu Cc: Xinliang David Li , Jan Hubicka , "gcc@gcc.gnu.org" , Wei Mi , Eugene Rozenfeld , Wenlei He Subject: Re: State of AutoFDO in GCC Message-ID: <20210426191345.GB1401198@tassilo.jf.intel.com> References: <20210423192834.GA1949@kam.mff.cuni.cz> <20210425190754.GA88857@kam.mff.cuni.cz> <87a6plulkz.fsf@linux.intel.com> <20210426180011.GA1401198@tassilo.jf.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Spam-Status: No, score=-1.0 required=5.0 tests=BAYES_00, KAM_DMARC_STATUS, KAM_LAZY_DOMAIN_SECURITY, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=no autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: gcc@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 26 Apr 2021 19:13:49 -0000 On Mon, Apr 26, 2021 at 06:40:56PM +0000, Hongtao Yu wrote: > Andi, thanks for pointing out the perf script issues. Can you please > elaborate a bit on the exact issue you have seen? We’ve been using > specific output of perf script such as mmap, LBR and callstack events > filtered by process id. It works fine so far but may certainly hit issues > in the future with extended uses. The main problem is that you cannot just split the output in fields because some fields (like file names or process names) can have spaces without any kind of delimeter. It's possible to work around this, but tends to be fragile and ugly. Also there were occasional changes in the output the past. -Andi