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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