[Beowulf] how cluster's storage can be flexible/expandable?

[Jesse Becker]

On Tue, Nov 13, 2012 at 03:17:12PM -0500, Greg Keller wrote:
>
>From: Joe Landman <landman at scalableinformatics.com<mailto:landman at scalableinformatics.com>>
>That's not the issue with glusterfs.  It's distributed metadata architecture is a double edged sword.  Very good for distributed data, very very bad for metadata heavy ops.
>
>That and the xfs attributes haven't been slow in years though some folks like bringing up the old behavior pre 2.6.26 as examples of why you shouldn't use it.   Dave Chinner has a great presentation on the topic from 15 months ago or so.  Puts down real numbers.  Situation is rather different than implied.
>
>
>We've recently seen XFS kill a pretty important server after an abrupt power off.  It appears someone decided they needed to force it to be "POSIX" compliant by default, and as a result XFS doesn't sync/flush to disk unless told to or some rather long timeout (30 seconds can be verrry long ).
>
>Has anyone else seen this / been surprised / re-tuned / written the how-to for me?

On the other hand...

We use XFS for several hundred TB of files (in multiple separate 20 or
40TB filesystems), and haven't had a serious XFS-related problem since we
started using it ~5 or 6 years ago.



-- 
Jesse Becker
NHGRI Linux support (Digicon Contractor)