[Gluster-devel] GlusterFS 3.0pre1 (Whats in 3.0)

[Anand Avati]

> > Key highlights of 3.0 are
> > * Background self-healing: Applications won't be blocked any more during
> healing operation.
> > * Checksum based healing: Rsync like healing mechanism to heal only the
> inconsistent blocks within a file.
> > * Healing on the fly: Files can be healed even when the files are open and
> application is performing active I/O.
> > * Generation numbers: Self-healing can now reliably handle tricky corner
> cases (such as "rm -rf" bug).
> >
>
>  Great list! I assume direct-io will be supported for virtualization as
> well? The above and disable-direct-io are the last things keeping us from
> launching Gluster on our Xen cluster.

direct-io-mode for better write-performance is needed only on kernels
< 2.6.27, and direct-io-mode is inharently incompatible with many
other functionalities (like mmap, aio, running VMs). If you have a
newer kernel, glusterfs-3.0 does not honor
--disable/enable-direct-io-mode and always "works fast".

Avati