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=-2.1 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID, USER_AGENT_MUTT autolearn=ham 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 20203C43144 for ; Thu, 28 Jun 2018 22:59:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CDE172442A for ; Thu, 28 Jun 2018 22:59:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=thunk.org header.i=@thunk.org header.b="n8S7nMm9" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CDE172442A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=mit.edu Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S967454AbeF1W7H (ORCPT ); Thu, 28 Jun 2018 18:59:07 -0400 Received: from imap.thunk.org ([74.207.234.97]:38266 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966992AbeF1W7A (ORCPT ); Thu, 28 Jun 2018 18:59:00 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=thunk.org; s=ef5046eb; h=In-Reply-To:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=iVDme/GCjfCxcBU4mkvrUdc4aot7Ors2C8p49qn6Ng8=; b=n8S7nMm9Km/QkPgbRNqnXJEynG EToAmSG4UH0CZwgEYJ2wAT8NRZSe+jk4b7+jSvJCk6Ly9O2JDPLKUWnqaHQ6j703F0t7sh66uyK5x b3YBxWGzH/lJmeJC0LvFSX8KxZ5e4n4tslfEVbsGkMPtKmcvWwSXrKAlfHdGfADtIbP8=; Received: from root (helo=callcc.thunk.org) by imap.thunk.org with local-esmtp (Exim 4.89) (envelope-from ) id 1fYfsQ-000362-6I; Thu, 28 Jun 2018 22:58:58 +0000 Received: by callcc.thunk.org (Postfix, from userid 15806) id 5CE087A4480; Thu, 28 Jun 2018 18:58:57 -0400 (EDT) Date: Thu, 28 Jun 2018 18:58:57 -0400 From: "Theodore Y. Ts'o" To: Steve French Cc: linux-fsdevel , LKML , samba-technical , CIFS Subject: Re: config files and how to have persistent Linux kernel Driver/File System configuration info saved Message-ID: <20180628225857.GB1231@thunk.org> Mail-Followup-To: "Theodore Y. Ts'o" , Steve French , linux-fsdevel , LKML , samba-technical , CIFS References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.0 (2018-05-17) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: tytso@thunk.org X-SA-Exim-Scanned: No (on imap.thunk.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 28, 2018 at 05:37:15PM -0500, Steve French wrote: > Ronnie brought up an interesting point about the problems consistently > configuring file systems (or any Linux module for that matter) so that > reboot doesn't wipe away security or performance tuning changes. In general it's considered best practice to make the file system auto-tune itself as much as possible, because the sad fact is that 99.9999% of the customers aren't going to bother to add any tuning parameters. So there hasn't been a push to try to create something more complex, because it's generally not needed. Settings via /sys/fs/ext4 are generally for developers as they try to understand how things work, so they can improve the file systems defaults / auto-tuning algorithms. - Ted