[Beowulf] Building new cluster - estimate

[Chris Samuel]

----- "Matt Lawrence" <matt at technoronin.com> wrote:

> I have never had any problems with ext3.

I suspect you're not doing a lot of disk I/O, we
found NFS servers using ext3 as a back end would
crumble under the weight of lots of writes as ext3
is single threaded through the journal daemon.

That means that you end up with all your NFS daemons
blocking on that, stalling everything else. :-(

> I had dinner with a friend who is an expert Linux
> sysadmin who was warning me to stay away from xfs.

There have been occasional bugs in XFS in older kernel
releases, but then there have been bugs in other filesystems
too.

> He cited lots of fragmentation problems that routinely
> locked up his systems. 

Never had that problem here.

Does he know that he can use xfs_fsr to defragment
XFS filesystems online ?

Is he sure he's not hitting another kernel bug ?

cheers,
Chris
-- 
Christopher Samuel - (03) 9925 4751 - Systems Manager
 The Victorian Partnership for Advanced Computing
 P.O. Box 201, Carlton South, VIC 3053, Australia
VPAC is a not-for-profit Registered Research Agency