From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugzilla-daemon@bugzilla.kernel.org Subject: [Bug 86471] drastic reduction of write performance after the termination of mysqld Date: Wed, 22 Oct 2014 20:22:55 +0000 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit To: linux-ext4@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.19.201]:42383 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932150AbaJVUW6 (ORCPT ); Wed, 22 Oct 2014 16:22:58 -0400 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 4BE072026C for ; Wed, 22 Oct 2014 20:22:57 +0000 (UTC) Received: from bugzilla2.web.kernel.org (bugzilla2.web.kernel.org [172.20.200.52]) by mail.kernel.org (Postfix) with ESMTP id C28F02025B for ; Wed, 22 Oct 2014 20:22:55 +0000 (UTC) In-Reply-To: Sender: linux-ext4-owner@vger.kernel.org List-ID: https://bugzilla.kernel.org/show_bug.cgi?id=86471 --- Comment #4 from Theodore Tso --- Are you sure this is actually a problem? Could it just be that when mysqld shuts down, it's issuing a huge number of buffered writes which is just taking a long, long time to get written out to your eMMC device (which is typically very, *very* slow to handle writes). I had suggested using blktrace to see if I/O is going on. You could also try looking using iostat or the dstat program. If it's just that I/O is still happening, then things may be working normally --- just that eMMC might be a bad match with a high performance database workload. -- You are receiving this mail because: You are watching the assignee of the bug.