[CentOS] 11TB ext4 filesystem - filesystem alternatives?

Fri Sep 28 23:30:26 UTC 2012
James A. Peltier <jpeltier at sfu.ca>

----- Original Message -----
| Hello,
| 
| One day our servers farm rebooted unexpectedly (power fail happened)
| and on centos 6.3 with up2date kernel we lost few hundred files
| (which
| probably was opened for reading, NOT writing) on XFS.
| 
| Unexpected power lost follow to situation when some files get a zero
| size.

This is not uncommon with a file system like XFS, where the file system makes EXTENSIVE use of file system caching and memory and internal semantics that will make your head spin.  Fact of the matter is, that in spite of this "possibility" of loss, XFS is by far the best file system for large volumes at the moment and especially during initialization time.  You *can* use EXT4 with you can speed this up if you use the -E lazy_itable_init=1 -O dir_index,extent,flex_bg,uninit_bg options.

-- 
James A. Peltier
Manager, IT Services - Research Computing Group
Simon Fraser University - Burnaby Campus
Phone   : 778-782-6573
Fax     : 778-782-3045
E-Mail  : jpeltier at sfu.ca
Website : http://www.sfu.ca/itservices
          http://blogs.sfu.ca/people/jpeltier

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