From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan Priebe - Profihost AG Subject: syncfs slower than without syncfs Date: Wed, 07 Nov 2012 10:41:58 +0100 Message-ID: <509A2CE6.1010100@profihost.ag> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail.profihost.ag ([85.158.179.208]:33567 "EHLO mail.profihost.ag" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751938Ab2KGJmG (ORCPT ); Wed, 7 Nov 2012 04:42:06 -0500 Sender: ceph-devel-owner@vger.kernel.org List-ID: To: "ceph-devel@vger.kernel.org" Hello list, syncfs is much slower than without syncfs to me. If i compile latest ceph master with wip-rbd-read: with syncfs: rand 4K: write: io=1133MB, bw=12853KB/s, iops=3213, runt= 90277msec read : io=1239MB, bw=14046KB/s, iops=3511, runt= 90325msec seq 4M: write: io=37560MB, bw=423874KB/s, iops=103, runt= 90738msec read : io=103852MB, bw=1151MB/s, iops=287, runt= 90237msec without syncfs: rand 4K: write: io=3733MB, bw=42459KB/s, iops=10614, runt= 90039msec read : io=6018MB, bw=68446KB/s, iops=17111, runt= 90038msec seq 4M: write: io=51204MB, bw=577328KB/s, iops=140, runt= 90820msec read : io=150320MB, bw=1666MB/s, iops=416, runt= 90228msec I thought syncfs should boost the performance. Greets, Stefan