From: Kirill Korotaev Subject: Re: container disk quota Date: Sat, 2 Jun 2012 19:21:17 +0400 Message-ID: <8660DDAA-D7A7-4C03-8CBB-9DB7E94C80CB@parallels.com> References: <1338389946-13711-1-git-send-email-jeff.liu@oracle.com> <20120601155457.GA30909@quack.suse.cz> <20120601160421.GA17402@amd1> <4FC9ABBB.3050303@oracle.com> <01FED15D-15A3-4542-B95B-1166F0A309E6@parallels.com> <4FC9B183.10605@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Jan Kara , "tytso-3s7WtUTddSA@public.gmane.org" , "tinguely-sJ/iWh9BUns@public.gmane.org" , "containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org" , "david-FqsqvQoI3Ljby3iVrkZq2A@public.gmane.org" , "hch-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org" , "bpm-sJ/iWh9BUns@public.gmane.org" , "christopher.jones-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org" , "linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "tm-d1IQDZat3X0@public.gmane.org" , "linux-ext4-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "chris.mason-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org" To: "jeff.liu-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org" Return-path: In-Reply-To: <4FC9B183.10605-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org> Content-Language: en-US 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 List-Id: linux-ext4.vger.kernel.org >>>> >>>> Not having looked closely at the original patchset, let me ask - is this >>>> feature going to be a freebie with Eric's usernamespace patches? >>> >>> It we can reach a consensus to bind quota on mount namespace for >>> container or other things maybe. >> >> 1. OpenVZ doesn't use mount namespaces and still has quotas per container. > > AFAICS, OpenVZ has self-released quota tools to supply this feature. but standard quota tools work inside container w/o any modifications. This is very important for us, cause we run unmodified distros inside. Actually, this is unrelated. I meant that OpenVZ needs ability to have group quotas w/o mount namespaces. > >> >> 2. BTW, have you seen Dmitry Monakhov patches for same containers quotas via additional inode attribute? it allows to make it journaled. > > You means the directly/project quota on ext4? > If yes, I have observed this feature back to the end of last year in > EXT4 mail list. yes > >> How quotas are stored in your case? > > It simply cached at memory for now, it also can be tweak up to journaled > I think, if introducing corresponding routines quota_read/quota_write to > particular journal file system. just cached quotas are bad - you never sure they are correct. journaled quotas (as standart) are much better. > >> >> 3. I tend to think nowdays such quotas maybe of less need. Quota code doesn't scale well. And it's easier to put container in image file (as OpenVZ recently introduced). > > There have such requirements dropped to LXC mail list nowadays. > Directory quota is pretty cool and it also useful to containers perspective. > > However, that's two different quota mechanism. > > "Quota code doesn't scale well". > Do you means it have global locking mechanism and only quota structure > to bill up quota for all file systems with VFS quota enabled? yes. Kirill