OpenCloudOS-Kernel/Documentation/filesystems/ocfs2.txt

65 lines
2.3 KiB
Plaintext

OCFS2 filesystem
==================
OCFS2 is a general purpose extent based shared disk cluster file
system with many similarities to ext3. It supports 64 bit inode
numbers, and has automatically extending metadata groups which may
also make it attractive for non-clustered use.
You'll want to install the ocfs2-tools package in order to at least
get "mount.ocfs2" and "ocfs2_hb_ctl".
Project web page: http://oss.oracle.com/projects/ocfs2
Tools web page: http://oss.oracle.com/projects/ocfs2-tools
OCFS2 mailing lists: http://oss.oracle.com/projects/ocfs2/mailman/
All code copyright 2005 Oracle except when otherwise noted.
CREDITS:
Lots of code taken from ext3 and other projects.
Authors in alphabetical order:
Joel Becker <joel.becker@oracle.com>
Zach Brown <zach.brown@oracle.com>
Mark Fasheh <mark.fasheh@oracle.com>
Kurt Hackel <kurt.hackel@oracle.com>
Sunil Mushran <sunil.mushran@oracle.com>
Manish Singh <manish.singh@oracle.com>
Caveats
=======
Features which OCFS2 does not support yet:
- extended attributes
- quotas
- cluster aware flock
- cluster aware lockf
- Directory change notification (F_NOTIFY)
- Distributed Caching (F_SETLEASE/F_GETLEASE/break_lease)
- POSIX ACLs
- readpages / writepages (not user visible)
Mount options
=============
OCFS2 supports the following mount options:
(*) == default
barrier=1 This enables/disables barriers. barrier=0 disables it,
barrier=1 enables it.
errors=remount-ro(*) Remount the filesystem read-only on an error.
errors=panic Panic and halt the machine if an error occurs.
intr (*) Allow signals to interrupt cluster operations.
nointr Do not allow signals to interrupt cluster
operations.
atime_quantum=60(*) OCFS2 will not update atime unless this number
of seconds has passed since the last update.
Set to zero to always update atime.
data=ordered (*) All data are forced directly out to the main file
system prior to its metadata being committed to the
journal.
data=writeback Data ordering is not preserved, data may be written
into the main file system after its metadata has been
committed to the journal.
preferred_slot=0(*) During mount, try to use this filesystem slot first. If
it is in use by another node, the first empty one found
will be chosen. Invalid values will be ignored.