From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from simark.ca by simark.ca with LMTP id 91X+KnqBlWB1SQAAWB0awg (envelope-from ) for ; Fri, 07 May 2021 14:05:46 -0400 Received: by simark.ca (Postfix, from userid 112) id A12861F11C; Fri, 7 May 2021 14:05:46 -0400 (EDT) X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on simark.ca X-Spam-Level: X-Spam-Status: No, score=-1.1 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.2 Received: from lists.lttng.org (lists.lttng.org [167.114.26.123]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by simark.ca (Postfix) with ESMTPS id 67BC41E01F for ; Fri, 7 May 2021 14:05:45 -0400 (EDT) Received: from lists-lttng01.efficios.com (localhost [IPv6:::1]) by lists.lttng.org (Postfix) with ESMTP id 4FcJK45bgkz1kCk; Fri, 7 May 2021 14:05:44 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=lists.lttng.org; s=default; t=1620410745; bh=XjmwK69kN23Ma6i76ZDCJPMIezx974+d8EuEC8JdhmU=; h=Date:To:Cc:References:In-Reply-To:Subject:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From:Reply-To:From; b=QRUO+ImYvOpvA4tW9zgvRd/UwjfOMERD65Vsk8zBBTcEyXB2QWGkqOlrrBmzGb00+ 51gWtfsSd5mnYPyCxVIlxrWfz4nQS3dTZ3rqeCMg9rnRgI7vUL4Tcx0DLZnN8/DEht RR7qLqVBHydwxcZezFwE9X50DQClY65UPie8R7C6EOdbdmCo361qgcAIyerHpsF4rc gYELMdHe6YOA/GmTwCUifGfYe7/NsdcURkbO4NdJn27xFbWK+kLjcksY3TazNRugz9 vuvu4iJFe8Wy6NB8Eu9n1xVNB5D7lj9+d6pauR06XNaO6PiWHhAwr5/24a0aQKTDGh beXOTZVlyANUw== Received: from mail.efficios.com (mail.efficios.com [167.114.26.124]) by lists.lttng.org (Postfix) with ESMTPS id 4FcJK34HKbz1kCj for ; Fri, 7 May 2021 14:05:43 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id 4A27F31C828 for ; Fri, 7 May 2021 14:05:37 -0400 (EDT) Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id Wpomee889_Qb; Fri, 7 May 2021 14:05:36 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id 4812431CAC2; Fri, 7 May 2021 14:05:36 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com 4812431CAC2 X-Virus-Scanned: amavisd-new at efficios.com Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id Uz2x9ZukFTgS; Fri, 7 May 2021 14:05:36 -0400 (EDT) Received: from joraj-alpa (unknown [107.159.43.215]) by mail.efficios.com (Postfix) with ESMTPSA id 1AB8731CB2B; Fri, 7 May 2021 14:05:36 -0400 (EDT) Date: Fri, 7 May 2021 14:05:32 -0400 To: Eqbal Cc: lttng-dev@lists.lttng.org Message-ID: <20210507180532.GA1227214@joraj-alpa> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Subject: Re: [lttng-dev] lttng live event loss with babeltrace2 X-BeenThere: lttng-dev@lists.lttng.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: LTTng development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Jonathan Rajotte-Julien via lttng-dev Reply-To: Jonathan Rajotte-Julien Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: lttng-dev-bounces@lists.lttng.org Sender: "lttng-dev" Hi, See https://github.com/lttng/lttng-tools/commit/c876d657fb08a91ca7c907b92f1b7604aee664ee . We would appreciate your feedback on this if possible based on your use case. Cheers On Mon, May 03, 2021 at 05:05:10PM -0700, Eqbal via lttng-dev wrote: > Hi, > > I have a lttng live session trace consumer application using libbabeltrace2 > where I create a graph to consume lttng live session traces and output to > another sink. I am running the graph in a loop at some polling interval as > long as I get BT_GRAPH_RUN_STATUS_AGAIN status. What I am noticing is that > if my polling interval is large enough I tend to lose either all or some of > the events. I experimented with various polling intervals and it seems if > the polling interval is less than *DELAYUS *from "lttng-create > --live=DELAYUS" option then I am able to get all the events, otherwise I > tend to lose events. > > Here are the steps I follow: > 1. start session daemon and relay daemon > 2. create a live session (with default delay of 1s), enable events and start > 3. Start my application (hello world example from lttng docs) > 4. Start the consumer application built using libbabeltrace that connects > to the live session > > I noticed that the events are actually persisted in the ~/lttng-traces by > the relay daemon, but it does not reach babeltrace consumer application. I > have noticed the same behavior with babeltrace2 cli. > > I would like to understand what is the reason for such behavior and if > playing with the polling interval in relation to the DELAYUS value is the > right thing to do. > > Thanks, > Eqbal > _______________________________________________ > lttng-dev mailing list > lttng-dev@lists.lttng.org > https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev -- Jonathan Rajotte-Julien EfficiOS _______________________________________________ lttng-dev mailing list lttng-dev@lists.lttng.org https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev