Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10
Hi, I had a confirmation that BTRFS backend storage will not be able to provide real disk information quota to the container because of the way BTRFS works with the kernel. I decided to move from BTRFS backend storage to ZFS backend storage . Using ZFS , quota and disk size into the container à working. For those that will need to do the same I share a small script I used to migrate data : https://github.com/givre/lxd_btrfs_to_zfs Cordialement, Benoît De: "Benoit GEORGELIN - Association Web4all" À: "lxc-users" Envoyé: Vendredi 1 Juillet 2016 12:06:57 Objet: Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10 I upgraded the system to Ubuntu 16.04, kernel downgraded to 4.4.0-28-generic ( I wanted to use Cgroup Namespaces ) BTRFS quotas looks to work properly , system is stable . Cordialement, Benoît De: "Benoit GEORGELIN - Association Web4all" À: "lxc-users" Envoyé: Jeudi 30 Juin 2016 11:01:50 Objet: Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10 Thanks for the information but it dosen't work for me with btrfs It correctly set the value on btrfs limit but no changes inside the container lxc config device set benltsp root size 10GB btrfs qg show -r -e /var/lib/lxd/containers/ -p -c|grep 443 0/443 9.01GiB 8.74GiB 10.00GiB 10.00GiB --- --- lxc config show benltsp [...] root: path: / size: 10GB type: disk lxc stop benltsp && lxc start benltsp lxc exec benltsp -- df -h Filesystem Size Used Avail Use% Mounted on /dev/sdb 100G 18G 80G 18% / none 492K 0 492K 0% /dev /dev/sdb 100G 18G 80G 18% /dev/lxd cgroup_root 10M 0 10M 0% /sys/fs/cgroup udev 480M 0 480M 0% /dev/tty tmpfs 497M 0 497M 0% /dev/shm tmpfs 497M 6.4M 490M 2% /run tmpfs 5.0M 0 5.0M 0% /run/lock Cordialement, Benoît G De: "McDonagh, Ed" À: "lxc-users" Envoyé: Jeudi 30 Juin 2016 10:25:20 Objet: Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10 >From https://www.stgraber.org/2016/03/26/lxd-2-0-resource-control-412/ lxc config device set my-container root size 20GB Works with ZFS and BTFS From: lxc-users [mailto:lxc-users-boun...@lists.linuxcontainers.org] On Behalf Of Benoit GEORGELIN - Association Web4all Sent: 30 June 2016 15:20 To: lxc-users Subject: Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10 Yes, I have to idea in mind. 1- Using ZFS I have to try how it looks with LXD/LXC. I wanted to give a try to btrfs . With ZFS , are you using quotas ? Can you tell me what "df -h" looks into your container ? With btrfs , the container see the disk size of the host, so you don't know how much space you are using, it's was not the best anyways. 2- LVM A the beginning, it's the solution I was using. Finally it was not that bad. By a script to create containers, I was doing : - Create a new LVM Volume - Mount the volume - Install the container with "dir path" So in the container you have one disk, it's the full size of the volume and act like a real disk including volume size information Cordialement, Benoît ____________________ De: "Sjoerd" À: "lxc-users" Envoyé: Jeudi 30 Juin 2016 10:06:03 Objet: Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10 On 30/06/2016 15:50, Benoit GEORGELIN - Association Web4all wrote: > Yesterday I tried the kernel:v4.6.3-yakkety > > The command "lxc stop container" totaly crash the system . Hard reboot > mandatory > > With v4.5.7-yakkety so far, everything looks fine, including the > quota. > But after what I read about btrfs, I'll find another FS for production > system ready because I need the quota Hmmm that doesn't sound prommising then :'( Anyway for my local server I use ZFS on Linux (Ubuntu 16.04). Maybe that's something for you too? I don't use ZFS on my VPS, cause it doesn't have enough RAM (just 1GB) Cheers, Sjoerd ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users # Attention: This e-mail and any attachment is for authorised use by the intended recipient(s) only. It may contain proprietary, confidential and/or privileged information and should not be copied, disclosed, distributed, retained or used by any other party. If you are not an intended recipient please notify the sender immediately and delete this e-mail (including attachments and copies). The statements and opinions expressed in this e-mail are those of the author and do not necessarily reflect those of the Royal Marsden NHS Foundation Trust. The Trust does not take any responsibility for the statements and opinions of the author. Website: http://www.royalmarsden.nhs.uk ###
Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10
I upgraded the system to Ubuntu 16.04, kernel downgraded to 4.4.0-28-generic ( I wanted to use Cgroup Namespaces ) BTRFS quotas looks to work properly , system is stable . Cordialement, Benoît De: "Benoit GEORGELIN - Association Web4all" À: "lxc-users" Envoyé: Jeudi 30 Juin 2016 11:01:50 Objet: Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10 Thanks for the information but it dosen't work for me with btrfs It correctly set the value on btrfs limit but no changes inside the container lxc config device set benltsp root size 10GB btrfs qg show -r -e /var/lib/lxd/containers/ -p -c|grep 443 0/443 9.01GiB 8.74GiB 10.00GiB 10.00GiB --- --- lxc config show benltsp [...] root: path: / size: 10GB type: disk lxc stop benltsp && lxc start benltsp lxc exec benltsp -- df -h Filesystem Size Used Avail Use% Mounted on /dev/sdb 100G 18G 80G 18% / none 492K 0 492K 0% /dev /dev/sdb 100G 18G 80G 18% /dev/lxd cgroup_root 10M 0 10M 0% /sys/fs/cgroup udev 480M 0 480M 0% /dev/tty tmpfs 497M 0 497M 0% /dev/shm tmpfs 497M 6.4M 490M 2% /run tmpfs 5.0M 0 5.0M 0% /run/lock Cordialement, Benoît G De: "McDonagh, Ed" À: "lxc-users" Envoyé: Jeudi 30 Juin 2016 10:25:20 Objet: Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10 >From https://www.stgraber.org/2016/03/26/lxd-2-0-resource-control-412/ lxc config device set my-container root size 20GB Works with ZFS and BTFS From: lxc-users [mailto:lxc-users-boun...@lists.linuxcontainers.org] On Behalf Of Benoit GEORGELIN - Association Web4all Sent: 30 June 2016 15:20 To: lxc-users Subject: Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10 Yes, I have to idea in mind. 1- Using ZFS I have to try how it looks with LXD/LXC. I wanted to give a try to btrfs . With ZFS , are you using quotas ? Can you tell me what "df -h" looks into your container ? With btrfs , the container see the disk size of the host, so you don't know how much space you are using, it's was not the best anyways. 2- LVM A the beginning, it's the solution I was using. Finally it was not that bad. By a script to create containers, I was doing : - Create a new LVM Volume - Mount the volume - Install the container with "dir path" So in the container you have one disk, it's the full size of the volume and act like a real disk including volume size information Cordialement, Benoît ____________ De: "Sjoerd" À: "lxc-users" Envoyé: Jeudi 30 Juin 2016 10:06:03 Objet: Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10 On 30/06/2016 15:50, Benoit GEORGELIN - Association Web4all wrote: > Yesterday I tried the kernel:v4.6.3-yakkety > > The command "lxc stop container" totaly crash the system . Hard reboot > mandatory > > With v4.5.7-yakkety so far, everything looks fine, including the > quota. > But after what I read about btrfs, I'll find another FS for production > system ready because I need the quota Hmmm that doesn't sound prommising then :'( Anyway for my local server I use ZFS on Linux (Ubuntu 16.04). Maybe that's something for you too? I don't use ZFS on my VPS, cause it doesn't have enough RAM (just 1GB) Cheers, Sjoerd ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users # Attention: This e-mail and any attachment is for authorised use by the intended recipient(s) only. It may contain proprietary, confidential and/or privileged information and should not be copied, disclosed, distributed, retained or used by any other party. If you are not an intended recipient please notify the sender immediately and delete this e-mail (including attachments and copies). The statements and opinions expressed in this e-mail are those of the author and do not necessarily reflect those of the Royal Marsden NHS Foundation Trust. The Trust does not take any responsibility for the statements and opinions of the author. Website: http://www.royalmarsden.nhs.uk # ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users
Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10
Thanks for the information but it dosen't work for me with btrfs It correctly set the value on btrfs limit but no changes inside the container lxc config device set benltsp root size 10GB btrfs qg show -r -e /var/lib/lxd/containers/ -p -c|grep 443 0/443 9.01GiB 8.74GiB 10.00GiB 10.00GiB --- --- lxc config show benltsp [...] root: path: / size: 10GB type: disk lxc stop benltsp && lxc start benltsp lxc exec benltsp -- df -h Filesystem Size Used Avail Use% Mounted on /dev/sdb 100G 18G 80G 18% / none 492K 0 492K 0% /dev /dev/sdb 100G 18G 80G 18% /dev/lxd cgroup_root 10M 0 10M 0% /sys/fs/cgroup udev 480M 0 480M 0% /dev/tty tmpfs 497M 0 497M 0% /dev/shm tmpfs 497M 6.4M 490M 2% /run tmpfs 5.0M 0 5.0M 0% /run/lock Cordialement, Benoît G De: "McDonagh, Ed" À: "lxc-users" Envoyé: Jeudi 30 Juin 2016 10:25:20 Objet: Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10 >From https://www.stgraber.org/2016/03/26/lxd-2-0-resource-control-412/ lxc config device set my-container root size 20GB Works with ZFS and BTFS From: lxc-users [mailto:lxc-users-boun...@lists.linuxcontainers.org] On Behalf Of Benoit GEORGELIN - Association Web4all Sent: 30 June 2016 15:20 To: lxc-users Subject: Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10 Yes, I have to idea in mind. 1- Using ZFS I have to try how it looks with LXD/LXC. I wanted to give a try to btrfs . With ZFS , are you using quotas ? Can you tell me what "df -h" looks into your container ? With btrfs , the container see the disk size of the host, so you don't know how much space you are using, it's was not the best anyways. 2- LVM A the beginning, it's the solution I was using. Finally it was not that bad. By a script to create containers, I was doing : - Create a new LVM Volume - Mount the volume - Install the container with "dir path" So in the container you have one disk, it's the full size of the volume and act like a real disk including volume size information Cordialement, Benoît De: "Sjoerd" À: "lxc-users" Envoyé: Jeudi 30 Juin 2016 10:06:03 Objet: Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10 On 30/06/2016 15:50, Benoit GEORGELIN - Association Web4all wrote: > Yesterday I tried the kernel:v4.6.3-yakkety > > The command "lxc stop container" totaly crash the system . Hard reboot > mandatory > > With v4.5.7-yakkety so far, everything looks fine, including the > quota. > But after what I read about btrfs, I'll find another FS for production > system ready because I need the quota Hmmm that doesn't sound prommising then :'( Anyway for my local server I use ZFS on Linux (Ubuntu 16.04). Maybe that's something for you too? I don't use ZFS on my VPS, cause it doesn't have enough RAM (just 1GB) Cheers, Sjoerd ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users # Attention: This e-mail and any attachment is for authorised use by the intended recipient(s) only. It may contain proprietary, confidential and/or privileged information and should not be copied, disclosed, distributed, retained or used by any other party. If you are not an intended recipient please notify the sender immediately and delete this e-mail (including attachments and copies). The statements and opinions expressed in this e-mail are those of the author and do not necessarily reflect those of the Royal Marsden NHS Foundation Trust. The Trust does not take any responsibility for the statements and opinions of the author. Website: http://www.royalmarsden.nhs.uk # ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users
Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10
From https://www.stgraber.org/2016/03/26/lxd-2-0-resource-control-412/ lxc config device set my-container root size 20GB Works with ZFS and BTFS From: lxc-users [mailto:lxc-users-boun...@lists.linuxcontainers.org] On Behalf Of Benoit GEORGELIN - Association Web4all Sent: 30 June 2016 15:20 To: lxc-users Subject: Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10 Yes, I have to idea in mind. 1- Using ZFS I have to try how it looks with LXD/LXC. I wanted to give a try to btrfs . With ZFS , are you using quotas ? Can you tell me what "df -h" looks into your container ? With btrfs , the container see the disk size of the host, so you don't know how much space you are using, it's was not the best anyways. 2- LVM A the beginning, it's the solution I was using. Finally it was not that bad. By a script to create containers, I was doing : - Create a new LVM Volume - Mount the volume - Install the container with "dir path" So in the container you have one disk, it's the full size of the volume and act like a real disk including volume size information Cordialement, Benoît De: "Sjoerd" À: "lxc-users" Envoyé: Jeudi 30 Juin 2016 10:06:03 Objet: Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10 On 30/06/2016 15:50, Benoit GEORGELIN - Association Web4all wrote: > Yesterday I tried the kernel:v4.6.3-yakkety > > The command "lxc stop container" totaly crash the system . Hard reboot > mandatory > > With v4.5.7-yakkety so far, everything looks fine, including the > quota. > But after what I read about btrfs, I'll find another FS for production > system ready because I need the quota Hmmm that doesn't sound prommising then :'( Anyway for my local server I use ZFS on Linux (Ubuntu 16.04). Maybe that's something for you too? I don't use ZFS on my VPS, cause it doesn't have enough RAM (just 1GB) Cheers, Sjoerd ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users # Attention: This e-mail and any attachment is for authorised use by the intended recipient(s) only. It may contain proprietary, confidential and/or privileged information and should not be copied, disclosed, distributed, retained or used by any other party. If you are not an intended recipient please notify the sender immediately and delete this e-mail (including attachments and copies). The statements and opinions expressed in this e-mail are those of the author and do not necessarily reflect those of the Royal Marsden NHS Foundation Trust. The Trust does not take any responsibility for the statements and opinions of the author. Website: http://www.royalmarsden.nhs.uk # ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users
Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10
Yes, I have to idea in mind. 1- Using ZFS I have to try how it looks with LXD/LXC. I wanted to give a try to btrfs . With ZFS , are you using quotas ? Can you tell me what "df -h" looks into your container ? With btrfs , the container see the disk size of the host, so you don't know how much space you are using, it's was not the best anyways. 2- LVM A the beginning, it's the solution I was using. Finally it was not that bad. By a script to create containers, I was doing : - Create a new LVM Volume - Mount the volume - Install the container with "dir path" So in the container you have one disk, it's the full size of the volume and act like a real disk including volume size information Cordialement, Benoît De: "Sjoerd" À: "lxc-users" Envoyé: Jeudi 30 Juin 2016 10:06:03 Objet: Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10 On 30/06/2016 15:50, Benoit GEORGELIN - Association Web4all wrote: > Yesterday I tried the kernel:v4.6.3-yakkety > > The command "lxc stop container" totaly crash the system . Hard reboot > mandatory > > With v4.5.7-yakkety so far, everything looks fine, including the > quota. > But after what I read about btrfs, I'll find another FS for production > system ready because I need the quota Hmmm that doesn't sound prommising then :'( Anyway for my local server I use ZFS on Linux (Ubuntu 16.04). Maybe that's something for you too? I don't use ZFS on my VPS, cause it doesn't have enough RAM (just 1GB) Cheers, Sjoerd ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users
Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10
On 30/06/2016 15:50, Benoit GEORGELIN - Association Web4all wrote: Yesterday I tried the kernel:v4.6.3-yakkety The command "lxc stop container" totaly crash the system . Hard reboot mandatory With v4.5.7-yakkety so far, everything looks fine, including the quota. But after what I read about btrfs, I'll find another FS for production system ready because I need the quota Hmmm that doesn't sound prommising then :'( Anyway for my local server I use ZFS on Linux (Ubuntu 16.04). Maybe that's something for you too? I don't use ZFS on my VPS, cause it doesn't have enough RAM (just 1GB) Cheers, Sjoerd ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users
Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10
Yesterday I tried the kernel:v4.6.3-yakkety The command "lxc stop container" totaly crash the system . Hard reboot mandatory With v4.5.7-yakkety so far, everything looks fine, including the quota. But after what I read about btrfs, I'll find another FS for production system ready because I need the quota Cordialement, Benoît G De: "Sjoerd" À: "lxc-users" Envoyé: Jeudi 30 Juin 2016 08:14:40 Objet: Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10 On 30/06/2016 12:03, Tomasz Chmielewski wrote: > "out of space" when doing snapshot affects kernels older than 4.6, no > matter if you use RAID-1, RAID-5/6, or no RAID. > > It's especially annoying especially when snapshotting running > containers with postgres, mysql, mongo etc. - as this causes database > errors or crashes. Hmm didn't know that yet, so I'll have upgrade to kernel 4.6.x then (running on 4.4.0-24 now) Thanks for the info! Cheers, Sjoerd ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users
Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10
On 30/06/2016 12:03, Tomasz Chmielewski wrote: "out of space" when doing snapshot affects kernels older than 4.6, no matter if you use RAID-1, RAID-5/6, or no RAID. It's especially annoying especially when snapshotting running containers with postgres, mysql, mongo etc. - as this causes database errors or crashes. Hmm didn't know that yet, so I'll have upgrade to kernel 4.6.x then (running on 4.4.0-24 now) Thanks for the info! Cheers, Sjoerd ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users
Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10
On 2016-06-30 18:55, Sjoerd wrote: On 30/06/2016 11:17, Tomasz Chmielewski wrote: Please note that btrfs is not a stable filesystem, at least not in the latest Ubuntu (16.04). You may have "out of space" errors with them, especially when doing snapshots. kernels 4.6.x[1] behave stable for me. I am not using RAID5/6 with btrfs. Only the latter is still not production ready as I understood it. My amount of snapshots won't be a lot (maybe 50 max or so), since I delete them regurly. But I'll keep an eye on the metadata as well indeed.thanks for the hint.. "out of space" when doing snapshot affects kernels older than 4.6, no matter if you use RAID-1, RAID-5/6, or no RAID. It's especially annoying especially when snapshotting running containers with postgres, mysql, mongo etc. - as this causes database errors or crashes. Tomasz Chmielewski http://wpkg.org/ ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users
Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10
On 30/06/2016 11:17, Tomasz Chmielewski wrote: Please note that btrfs is not a stable filesystem, at least not in the latest Ubuntu (16.04). You may have "out of space" errors with them, especially when doing snapshots. kernels 4.6.x[1] behave stable for me. I am not using RAID5/6 with btrfs. Only the latter is still not production ready as I understood it. My amount of snapshots won't be a lot (maybe 50 max or so), since I delete them regurly. But I'll keep an eye on the metadata as well indeed.thanks for the hint.. ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users
Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10
On 2016-06-30 17:38, Sjoerd wrote: On 29/06/2016 20:02, Benoit GEORGELIN - Association Web4all wrote: Hi, (without hijacking another thread) I'm sharing with you some information about BTRFS and Ubuntu 15.10, Kernel 4.2.0-30-generic regarding a quota disk error on my LXC containers If you plan tu use quota, this will be interesting for you to know. Yes I just read it on the btrfs-mailinglist ;) Anway besides the problems you describe, using quota also brings down btrfs send/receive speed to a crawl. I am backing up my containers with btrfs send/receive and because of all the quota problems described I am not using it anymore. Please note that btrfs is not a stable filesystem, at least not in the latest Ubuntu (16.04). You may have "out of space" errors with them, especially when doing snapshots. kernels 4.6.x[1] behave stable for me. [1] working with Ubuntu, from http://kernel.ubuntu.com/~kernel-ppa/mainline/ Tomasz Chmielewski http://wpkg.org/ ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users
Re: [lxc-users] Btrfs - Disk quota and Ubuntu 15.10
On 29/06/2016 20:02, Benoit GEORGELIN - Association Web4all wrote: Hi, (without hijacking another thread) I'm sharing with you some information about BTRFS and Ubuntu 15.10, Kernel 4.2.0-30-generic regarding a quota disk error on my LXC containers If you plan tu use quota, this will be interesting for you to know. Yes I just read it on the btrfs-mailinglist ;) Anway besides the problems you describe, using quota also brings down btrfs send/receive speed to a crawl. I am backing up my containers with btrfs send/receive and because of all the quota problems described I am not using it anymore. Cheers, ___ lxc-users mailing list lxc-users@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-users
[lxc-users] Btrfs - Disk quota and Ubuntu 15.10
Hi, (without hijacking another thread) I'm sharing with you some information about BTRFS and Ubuntu 15.10, Kernel 4.2.0-30-generic regarding a quota disk error on my LXC containers If you plan tu use quota, this will be interesting for you to know. Cheers -- Email sent to BTRFS list Hi dear users of the list. I'm new to the BTRFS file-system and I am having some problems with quotas I would like to share with you what I'm facing about "Disk quota exceeded" it's quite strange to me. - Description of the environment I have a BTRFS volume "/var/lib/lxd" I have some subvolume into "/var/lib/lxd/containers" The volume have quota enable Every subvolume have their quota groupe created Limit of 10Go has been set to every single subvolumes -The problem Randomly I can't write to some of the subvolumes anymore without having datas added into the subvolume. I can't figure why and the subvolumes are randomly not usable with the error : Disk quota exceeded I did delete all the quota groups, disable quota on the volume, enable the quota group again on the volume, check if quota groups were back automatically as btrfs version 4 is supposed to do I added back the limit 10Go Rescan Everything work just fine but some time after, I'm back to over-quota on some subvolumes. Thanks for your help on this. --One intéresting answer by Duncan: Hi dear users of the list. > > I'm new to the BTRFS file-system and I am having some problems with > quotas I would like to share with you what I'm facing about "Disk quota > exceeded" it's quite strange to me. Three points. 1) Btrfs quotas have a long history of trouble, both in correctness and in scaling ability (btrfs balances and checks can take far longer with quotas enabled, often too long to be practical), and if they are now stable, it's only a very recent development. As a result, my recommendation has been and remains not to use btrfs quotas unless you are specifically doing so to work with the devs to test and bugfix. If you don't need them, simply turn them off and leave them off until they are known to work. If you do actually need quota functionality, you're far better off using a filesystem where quotas are actually stable and work as intended. > - Description of the environment I have a BTRFS volume "/var/lib/lxd" > I have some subvolume into "/var/lib/lxd/containers" > > The volume have quota enable Every subvolume have their quota groupe > created Limit of 10Go has been set to every single subvolumes > > -The problem Randomly I can't write to some of the subvolumes anymore > without having datas added into the subvolume. > I can't figure why and the subvolumes are randomly not usable with the > error : Disk quota exceeded 2) I'm not sure of the current status here, but it's worth keeping in mind that unlike other filesystems, btrfs separates data and metadata, and it's possible for data to be under quota and still run out, if metadata takes you over quota. There was some talk a kernel cycle or two ago suggesting separating data and metadata quotas and allowing setting them either separately or overall capping them, but as I said, I'm not sure what the status is on that. > I did delete all the quota groups, disable quota on the volume, enable > the quota group again on the volume, check if quota groups were back > automatically as btrfs version 4 is supposed to do I added back the > limit 10Go Rescan Everything work just fine but some time after, I'm > back to over-quota on some subvolumes. > > Thanks for your help on this. > > Below, more details about the config and system point of view : > > > uname -a Linux lxd-virt-01b 4.2.0-30-generic #36-Ubuntu SMP Fri Feb 26 > 00:58:07 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux 3) Unfortunately, ubuntu chose what from upstream's viewpoint was a short- term-stable kernel. 4.2 is no longer supported upstream, and while it's possible that ubuntu is backporting as appropriate, on this list we track upstream and don't know what individual distros have backported and what they haven't. And I know for sure that 4.2 still had serious quota issues that are unlikely to have been fixed with backports because they never /did/ work right by 4.2, so the quota issues weren't regressions and thus patches to fix them would have been unlikely stable candidates. You thus have a few choices: 4.1 and 4.4 are upstream LTS series, and continue to be supported (tho I'd suggest 4.4 if you'll be adopting one, as btrfs is still developing fast enough that we only tend to well support the last couple LTS, and beyond that, while critical patches will be backported to the extent possible, if you have a problem you're still likely to be asked to upgrade and see if the problem is still there if you're out of that 2 LTS series window, and 4.1 is getting a bit long in the tooth to be just upgrading to now). So one choice is to move to the latest version of one of them. Anot
