From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751703AbcDTVW4 (ORCPT ); Wed, 20 Apr 2016 17:22:56 -0400 Received: from mail-yw0-f179.google.com ([209.85.161.179]:33046 "EHLO mail-yw0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751001AbcDTVWy (ORCPT ); Wed, 20 Apr 2016 17:22:54 -0400 Date: Wed, 20 Apr 2016 17:22:51 -0400 From: Tejun Heo To: zhong jiang Cc: Miao Xie , lizefan@huawei.com, dingxiang@huawei.com, LKML Subject: Re: A mainline question about cgroup writeback Message-ID: <20160420212251.GF4775@htj.duckdns.org> References: <5715DC1F.2020803@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5715DC1F.2020803@huawei.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 19, 2016 at 03:19:59PM +0800, zhong jiang wrote: > cgroup writeback support the filesystem both ext4 and ext2. > but, it appears to be not work when I test the function in the ext4. > The example is as follows: > echo "8:0 1048576" > blkio.throttle.write_bps_device > echo $$ > cgroup.procs > dd if=/dev/zero of=/test.c bs=1M count=10240 > 10240+0 records in > 10240+0 records out > 10737418240 bytes (11 GB) copied, 49.8796 s, 215 MB/s How much memory does the cgroup have available to it? It's buffered write. It might not get throttled if there are enough pages to dirty. Thanks. -- tejun