[PVE-User] Proxmox VE 3.4 and ZFS: Using compressionlz4 instead of compressionon by default

[Pongrácz István]

----------------eredeti üzenet-----------------
Feladó: "Daniel Mettler" mettlerd at numlock.ch 
Címzett: pve-user at pve.proxmox.com 
Dátum: Thu, 19 Mar 2015 00:31:58 +0100 (CET)
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> # zfs get compression
> NAME PROPERTY VALUE SOURCE
> rpool compression lz4 local
> rpool/ROOT compression lz4 inherited from rpool
> rpool/ROOT/pve-1 compression lz4 inherited from rpool
> rpool/swap compression lz4 inherited from rpool
>


Hi,

Just some notes:

* swap is not really a good idea on zfs (considering ARC, L2ARC, the memory overhead of them etc.). If possible, just do not use swap or put the swap on a different partition. It is dangerious if the available memory usually used and there are not so much free RAM.

* I use plain raw disk images with lz4 compression for storing KVM disks, instead of zvols. 
 Why?
 Because the filesystem layout will be simple, well known, simple for handling (backup, transfer to/from non-zfs systems).

* I use the following filesystem layout to store all CTs and VMs, templates, dumps:

zfsstorage1/vz (usually lz4 in all cases)
zfsstorage1/vz/dump (lz4 is not necessary if gzip/bzip2 used)
zfsstorage1/vz/images
zfsstorage1/vz/images/102
zfsstorage1/vz/images/104
zfsstorage1/vz/images/109
zfsstorage1/vz/images/200
zfsstorage1/vz/private
zfsstorage1/vz/private/101
zfsstorage1/vz/private/107
zfsstorage1/vz/private/124
zfsstorage1/vz/template (lz4 is not necessary, as everything already compressed: iso, tar.gz)

In some cases, containers could have more sub filesystems, for example storing DBs, webserver root directory or even for all virtual servers with different snapshot rules).

I found this comfortable and easy to understand/overview by other administrators.

What do you think?

Cheers,
István