From: Evgeniy Ivanov Subject: ext3/ext4 and waiting in do_get_write_access Date: Wed, 10 Nov 2010 13:34:30 +0300 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 To: linux-ext4@vger.kernel.org Return-path: Received: from mail-iw0-f174.google.com ([209.85.214.174]:63649 "EHLO mail-iw0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752276Ab0KJKeb (ORCPT ); Wed, 10 Nov 2010 05:34:31 -0500 Received: by iwn10 with SMTP id 10so622997iwn.19 for ; Wed, 10 Nov 2010 02:34:30 -0800 (PST) Sender: linux-ext4-owner@vger.kernel.org List-ID: Hi, I've two types of process: 15 RT small writers (2 page writers) and 3 hard writers. When I start hard writers RT processes start thrashing in do_get_write_access (waiting can be about 3-6s, but in normal situation it's expected to make writes in 50-100ms). I see the place, where we wait in do_get_write_access(). Are there anything to do with this problem, so I don't get problems with realtime processes? At least theoretically (I'm unfamiliar with journaling)? -- Evgeniy Ivanov