[Gluster-devel] glusterfs version3 and xen images

[Vikas Gorur]

Roland Fischer wrote:
> Hi,
>
> i think the algorithms doesnt work yet. I read the pdf -> 
> http://ftp.gluster.com/pub/gluster/glusterfs/3.0/LATEST/GlusterFS-3.0.0-Release-Notes.pdf 
>
>
> and this article is very interesting:
>
> The “Diff” algorithm is especially beneficial for situations such as 
> running VM images,
> where self-heal of a recovering replicated copy of the image will 
> occur much faster because
> only the changed blocks need to be synchronized.
>
> i use 12 GB (to 30GB) Xen Images and client side replication. If i 
> simulate an Hardwareerror on glusterfsserver 1 and after 5 minutes the 
> glusterfsserver 1 came back online, glusterfsserver2 starts sync but i 
> think not with "diff" algotihm ether with full!! i see the sync if i 
> do an iftop on both glusterfsserver.
>
> while syncing you cant do nothing in domU. no "df -h", no "ls" nothing 
> - you can do nothing. if the iftop on both glusterfsserver has reached 
> e.g. 12GB the domU works further.
>
> And thats the problem. in case of sync the domU must run further. This 
> is our destination.
>
Roland,

Thanks for all your input. We've been simulating the same situation 
ourselves and we do
see that self-heal appears to be slow. We'll post an update on the bug 
(bugzilla: 457) once we resolve the issue.


Vikas