filesystem with compression within a KVM

RobFantini

Famous Member
May 24, 2012
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Boston,Mass
Hello,

I've got a lot of text data to archive within KVM.

When the kvm is stored on zfs - the data takes up 1/2 the space of kvm on ceph. [ compression is turned on for zfs. I think it is on for ceph, however i do not see a setting in ceph.conf. which I'll ask about in a separate post.]

So I was thinking of using kvm on ceph with :
a small disk for opsys.
2ND disk using a file system which supports transparent compression like zfs or btrfs .

btrfs - I've never used it. zfs - have never tried as a single disk within a kvm.

If you have any suggestions / comments please reply.
 
regarding ceph compression - I did not have the following set, did so now. then will test compression result within a kvm:
Code:
ceph osd pool set ceph compression_mode passive
 
I have not been able to get ceph compression activated within a kvm or lxc.

using zfs within a kvm works

to test i rsynced logs from our rsyslog system to:

kvm on ceph using etx4: 6.6G
lxc on ceph; 6.6G
zfs in a kvm on ceph: 2.1G


If anyone has a suggestion on how ensure compression works with ceph [ I am sure it does and this is an operator error ] please send suggestions.