[lxc-users] Best backing store for 500 containers

[Ingvar Bogdahn]

Hi Fajar,

I believe the link you posted refers to the older implementations of lvm 
snapshots which has serious performance degradation. There is a newer 
implementation based on thin-provisiong device-mapper which seems quite 
promising, which is also blocked based afaik.
It doesn't test I/O performance but anyway interesting read (concerns 
docker):
http://developerblog.redhat.com/2014/09/30/overview-storage-scalability-docker/

One problem I have with them is that there are not directly usable with 
unprivileged containers. LVM operations need to be done by root or 
setcaps has to be changed.

ingvar



Am 30.06.15 um 13:17 schrieb Fajar A. Nugraha:
> I'm using ubuntu + zfs.
>
> Overlayfs has been part of mainline kernel since 3.18 (F22 uses
> 4.0.6). Latest overlayfs only works on top of ext4, so it's suitable
> if you don't want to reformat your existing fs. However using a union
> mount like overlayfs means you need to deal with its overhead (which
> includes a whole file is copied even if you only modify a small part
> of it).
>
> Btrfs is in active development, but seems to be the choice of many
> linux devs (including systemd developers).
>
> There seems to be performance issues with LVM snapshot (e.g.
> http://www.nikhef.nl/~dennisvd/lvmcrap.html)
>
> Choose whichever works best for you, do your own tests to make sure it
> performs within reasonable limits.
>