Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757613AbZDGD3W (ORCPT ); Mon, 6 Apr 2009 23:29:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752063AbZDGD3F (ORCPT ); Mon, 6 Apr 2009 23:29:05 -0400 Received: from acsinet11.oracle.com ([141.146.126.233]:31164 "EHLO acsinet11.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757501AbZDGD3E (ORCPT ); Mon, 6 Apr 2009 23:29:04 -0400 Subject: Re: [PATCH 0/8][RFC] IO latency/throughput fixes From: Chris Mason To: Linus Torvalds Cc: Jens Axboe , Linux Kernel Mailing List , tytso@mit.edu In-Reply-To: References: <1239022088-29002-1-git-send-email-jens.axboe@oracle.com> <20090406130414.GX5178@kernel.dk> Content-Type: text/plain Date: Mon, 06 Apr 2009 23:28:00 -0400 Message-Id: <1239074880.17426.7.camel@think.oraclecorp.com> Mime-Version: 1.0 X-Mailer: Evolution 2.24.1 Content-Transfer-Encoding: 7bit X-Source-IP: acsmt703.oracle.com [141.146.40.81] X-Auth-Type: Internal IP X-CT-RefId: str=0001.0A010204.49DAC84D.00C4:SCFMA4539814,ss=1,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1262 Lines: 35 On Mon, 2009-04-06 at 08:37 -0700, Linus Torvalds wrote: > > > One thing that I find intriguing is how the fsync time seems so > _consistent_ across a wild variety of drives. It's interesting how you see > delays that are roughly the same order of magnitude, even though you are > using an old SATA drive, and I'm using the Intel SSD. And when you turn > off TCQ, your numbers go down even more. > It may help if we rule out the ext3/jbd transaction growing code. I'd be pretty surprised if it made for long pauses, but its worth checking: -chris diff --git a/fs/jbd/transaction.c b/fs/jbd/transaction.c index e6a1174..a7c4f79 100644 --- a/fs/jbd/transaction.c +++ b/fs/jbd/transaction.c @@ -1417,7 +1417,7 @@ int journal_stop(handle_t *handle) * for joiners in that case. */ pid = current->pid; - if (handle->h_sync && journal->j_last_sync_writer != pid) { + if (0 && handle->h_sync && journal->j_last_sync_writer != pid) { u64 commit_time, trans_time; journal->j_last_sync_writer = pid; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/