[Linux-cluster] About GFS1 and I/O barriers.

[Mathieu Avila]

Hello all again,

More information on this topic:
http://lkml.org/lkml/2007/5/25/71

I guess the problem also applies to GFSS2.

--
Mathieu

Le Fri, 28 Mar 2008 15:34:58 +0100,
Mathieu Avila <mathieu.avila at seanodes.com> a écrit :

> Hello GFS team,
> 
> Some recent kernel developements have brought IO barriers into the
> kernel to prevent corruptions that could happen when blocks are being
> reordered before write, by the kernel or the block device itself, just
> before an electrical power failure.
> (on high-end block devices with UPS or NVRAM, those problems cannot
> happen)
> Some file systems implement them, notably ext3 and XFS. It seems to me
> that GFS1 has no such thing.
> 
> Do you plan to implement it ? If so, could the attached patch do the
> work ? It's incomplete : it would need a global tuning like
> fast_stafs, and a mount option like it's done for ext3. The code is
> mainly a copy-paste from JBD, and does a barrier only for journal
> meta-data. (should i do it for other meta-data ?)
> 
> Thanks,
> 
> --
> Mathieu
>