From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5A8EBD275; Thu, 9 Nov 2023 18:44:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="UQewXdR2" Received: from mail-pl1-x636.google.com (mail-pl1-x636.google.com [IPv6:2607:f8b0:4864:20::636]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D68673C10; Thu, 9 Nov 2023 10:44:50 -0800 (PST) Received: by mail-pl1-x636.google.com with SMTP id d9443c01a7336-1cc0d0a0355so10474265ad.3; Thu, 09 Nov 2023 10:44:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1699555490; x=1700160290; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:from:to:cc:subject:date:message-id :reply-to; bh=+u/67wjsdFPfi+3VMrpO879Jm3pGJagHTWGK5mUzdKA=; b=UQewXdR2bBAJzU4/NcmlB4LLefRD+Vs87YP1jMVQcNlh8mELXrr/xuEZGXNqTYrTgC 3DN8bevWy2tsyDyYbKIxs3ofOprWjNbkU9Hg7ON1p6QWCdfKy27S2HFdt4utWDBsbNhf DM65YKLy9L5P5PVCnBRw7dL0Voj2yfJMLpGeVwtLxjInkLjj6BWZADOqmJb9hzCscHWK 0B9S4kwSN5Wf7v4o2kC+4NOMXObEO0aejmehSIuKp4lwTMmXTlL7A72VuwaeIkamHZqQ 3BUpfgk6p/wMOnI4Ox9B5lSJUz52mv8oSxUPdDnc07YXYgz8/SlwRw6+1H1aCy88yoPH YYTw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1699555490; x=1700160290; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=+u/67wjsdFPfi+3VMrpO879Jm3pGJagHTWGK5mUzdKA=; b=kn325mTi/geOx6wEooIDZGQgrChlQSzPJ0tpYW5aFsHUEQ++4VSmo4j0aysBdAQeau cl93zdW7em9cGc/6cU/Sc+lJFBJ7kiAjRRa7+K7cQfXbjNTadjOSEQS+Vm7Toy9IU2Cn 6VY7gqDaRPko8XJ7+yRqv+sL6qwBz/dlg7g6p5+gWCUiRO0YlXYNCEgx5BTjfWRM4p4U atoSQ4nZ0f+WXVNYV8W81E1cCHY8GWdSQz430g00FQNGlyRurk2x09WXsM/yjAca2DGv j4RaDsg3SggmtSjBjFegAYZbU03rOdyTEHk93lo/yGIhXYqV7TJO2xdTnChgndLtRp1w Fnbg== X-Gm-Message-State: AOJu0YwNTMsMeNTdIuOrpBG6OJr6tI2YQvU05VTeC4KUmGsFeIuuZvRx 3A9tlwneWHDZ6ks4SQTyb4I= X-Google-Smtp-Source: AGHT+IFJHWritYKGihXbEEywurx0OvjBoYDD5T+xeqmeKKtVplLsozr1FibWtZf1pSI4siSBPeb1rg== X-Received: by 2002:a17:902:d486:b0:1cc:50f6:7fca with SMTP id c6-20020a170902d48600b001cc50f67fcamr7229515plg.24.1699555490067; Thu, 09 Nov 2023 10:44:50 -0800 (PST) Received: from localhost ([2620:10d:c090:400::4:7384]) by smtp.gmail.com with ESMTPSA id u7-20020a170902e5c700b001cc2f9fd74csm3828866plf.189.2023.11.09.10.44.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 09 Nov 2023 10:44:49 -0800 (PST) Sender: Tejun Heo Date: Thu, 9 Nov 2023 08:44:48 -1000 From: Tejun Heo To: Tycho Andersen Cc: cgroups@vger.kernel.org, linux-fsdevel@vger.kernel.org, Christian Brauner , Zefan Li , Johannes Weiner , Haitao Huang , Kamalesh Babulal Subject: Re: [RFC 0/6] tracking fd counts per cgroup Message-ID: References: <20231108002647.73784-1-tycho@tycho.pizza> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20231108002647.73784-1-tycho@tycho.pizza> Hello, On Tue, Nov 07, 2023 at 05:26:41PM -0700, Tycho Andersen wrote: > Hi all, > > At Netflix, we have a "canary" framework that will run test versions of > an application and automatically detect anomalies in various metrics. We > also have two "fleets", one full of virtual machines, and one that is a > multi-tenant container environment. > > On our full-VM fleet, one of the metrics we analyze is the number of open file > descriptors, from /proc/sys/fs/file-nr. However, no equivalent exists for the > multi-tenant container fleet, which has lead to several production issues. > > This idea is not new of course [1], but hopefully the existence of the new misc > cgroup will make it more tenable. > > I'm not really tied to any of the semantics in this series (e.g. threads could > be double counted even with a shared table), and am open to implementing this > in other ways if it makes more sense. As already raised by Christian, if the goal is monitoring, you should be able to do that easily with BPF. Thanks. -- tejun