From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vivek Goyal Subject: Re: [PATCHSET] blk-throttle: implement proper hierarchy support Date: Thu, 2 May 2013 13:34:28 -0400 Message-ID: <20130502173428.GA4771@redhat.com> References: <1367455189-6957-1-git-send-email-tj@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1367455189-6957-1-git-send-email-tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Tejun Heo Cc: axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org On Wed, May 01, 2013 at 05:39:18PM -0700, Tejun Heo wrote: [..] > While this patchset contains many patches, the implementation is > pretty straight-forward. throtl_grp's form a tree anchored at > throtl_data and bios climb the tree as they get dispatched at each > level. The bios which reach the top of the tree - throl_data - are > issued. Have a question here. Looks like when bio climbs from child group to parent group, then parent group slice starts fresh if parent was empty. So if we have a parent with 1MB/s limit and a child with 1MB/s limit and a bio gets queued in child, then looks like effective IO rate would be .5MB/s and not 1MB/s? IOW, when child gets queued, we should start time accounting for all parents in the hiearchy too. Thanks Vivek