From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Nelson Subject: Re: Slow file creating and deleting using bonnie ++ on Hammer Date: Tue, 26 May 2015 09:08:31 -0500 Message-ID: <55647E5F.7020100@redhat.com> References: <555F4C78.7060601@redhat.com> <55645FA3.3090507@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mx1.redhat.com ([209.132.183.28]:52415 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751280AbbEZOIm (ORCPT ); Tue, 26 May 2015 10:08:42 -0400 In-Reply-To: <55645FA3.3090507@redhat.com> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: John Spray , "Yan, Zheng" , Barclay Jameson Cc: Gregory Farnum , "ceph-devel@vger.kernel.org" On 05/26/2015 06:57 AM, John Spray wrote: > > > On 26/05/2015 07:55, Yan, Zheng wrote: >> the reason for slow file creations is that bonnie++ call fsync(2) >> after each creat(2). fsync() wait for safe replies of the create >> requests. MDS sends safe reply when log event for the request gets >> journaled safely. MDS flush the journal every 5 seconds >> (mds_tick_interval). So the speed of file creation for bonnie++ is one >> file every file seconds. > > Ah, I hadn't noticed that the benchmark called... I wonder if I'm seeing > the fuse client return quickly because it simply doesn't implement the > fsyncdir call. We should fix that! I seem to remember someone grumbling about this a while back but I don't really remember the details or who it was. :) > > It looks like we used to have an OP_FSYNC in the client-server protocol > (perhaps for flushing the log immediately on fsyncs), anyone have any > background on why that went away? > > Cheers, > John > -- > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html