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 Received: from lists.lttng.org (lists.lttng.org [167.114.26.123]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 18D05C43334 for ; Wed, 22 Jun 2022 13:20:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=lists.lttng.org; s=default; t=1655904008; bh=iHr/a1+Gkb6Fht+6GaRYxl9Jl10/R/UVbmHXRlOwssQ=; h=Date:To:Cc:In-Reply-To:References:Subject:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From:Reply-To:From; b=hCEwV/I89t2sxCvJjFfbTaF3MSVxccIkUU1Y0Euc3j+hnOopmrB6iSlR9MrP5WaUX +wmDNqEbAhB6j8gw4K9uuk8RpTyuc8fDXp3KQvPyybTCQs0PDebHJr6kwDyCUzvmYb urDmo2/Lcy9aFdV2AAvfZG2SLrf7Xpkn00MOWBGZaqE0eZqaANi0ATaE8+pOB4dzjc nGNCeV73Jk5b7FscsbKvZ8IejPskkyahzjbzA+1w0l+54wRsyePUpQ1uvSS8+xhIzN bnF0o/xxcLX/E321iw5yEXVqqLX4XAP42DGr83u9WbyPpWpxMypbFylispRhV78pBw 3wTf3J7B36uyQ== Received: from lists-lttng01.efficios.com (localhost [IPv6:::1]) by lists.lttng.org (Postfix) with ESMTP id 4LSkWr06v3zDRK; Wed, 22 Jun 2022 09:20:08 -0400 (EDT) Received: from mail.efficios.com (mail.efficios.com [167.114.26.124]) by lists.lttng.org (Postfix) with ESMTPS id 4LSkWp22FLzCTv for ; Wed, 22 Jun 2022 09:20:05 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id 8A5CC287D3F for ; Wed, 22 Jun 2022 09:19:59 -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 yEMZ-6euHPlw; Wed, 22 Jun 2022 09:19:59 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id 12BFD287D3D; Wed, 22 Jun 2022 09:19:59 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com 12BFD287D3D 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 zoEE0CFGIcbz; Wed, 22 Jun 2022 09:19:59 -0400 (EDT) Received: from mail03.efficios.com (mail03.efficios.com [167.114.26.124]) by mail.efficios.com (Postfix) with ESMTP id 07461287D3C; Wed, 22 Jun 2022 09:19:59 -0400 (EDT) Date: Wed, 22 Jun 2022 09:19:58 -0400 (EDT) To: Minlan Wang Cc: lttng-dev , paulmck Message-ID: <1420937751.21327.1655903998961.JavaMail.zimbra@efficios.com> In-Reply-To: <20220622074535.GA269641@localhost.localdomain>+6EDBC2C12E8A16E5> References: <20220614035533.GA174967@localhost.localdomain> <20220615034900.GA187807@localhost.localdomain> <396090936.61897.1655302558168.JavaMail.zimbra@efficios.com> <20220616080912.GA246781@localhost.localdomain> <1711122492.5944.1655473043420.JavaMail.zimbra@efficios.com> <20220621035206.GA267474@localhost.localdomain> <1843612610.17820.1655817158376.JavaMail.zimbra@efficios.com> <20220622074535.GA269641@localhost.localdomain> MIME-Version: 1.0 X-Originating-IP: [167.114.26.124] X-Mailer: Zimbra 8.8.15_GA_4304 (ZimbraWebClient - FF100 (Linux)/8.8.15_GA_4304) Thread-Topic: ***UNCHECKED*** Re: Re: urcu workqueue thread uses 99% of cpu while workqueue is empty Thread-Index: /dYvM5tb7eJkihrmAnXa3+eAc0+3EA== Subject: Re: [lttng-dev] ***UNCHECKED*** Re: Re: urcu workqueue thread uses 99% of cpu while workqueue is empty X-BeenThere: lttng-dev@lists.lttng.org X-Mailman-Version: 2.1.39 Precedence: list List-Id: LTTng development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Mathieu Desnoyers via lttng-dev Reply-To: Mathieu Desnoyers Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: lttng-dev-bounces@lists.lttng.org Sender: "lttng-dev" ----- On Jun 22, 2022, at 3:45 AM, Minlan Wang wangminlan@szsandstone.com wrote: [...] Hi Minlan, > -- > 1.8.3.1 > > > And the lttng session is configured to trace these events: > kernel: syscall futex On the kernel side, in addition to the syscall futex, I would really like to see what happens in the scheduler, mainly the wait/wakeup tracepoints. This can be added by using: lttng enable-event -k 'sched_*' This should help us confirm whether we indeed have a situation where queued wake ups happen to wake up a wait happening only later, which is unexpected by the current liburcu userspace code. [...] > --- > > The babletrace output of this session is pretty big, 6 MB in size, i put it in > the attachment trace_0622.tar.bz2. > Let my know if your mailbox can't handle such big attachment. It would be even better if you can share the binary trace, because then it's easy to load it in trace compass, cut away time ranges that don't matter, and lots of other useful stuff. Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com _______________________________________________ lttng-dev mailing list lttng-dev@lists.lttng.org https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev