Red Hat GFS 6.0 -, Administrator'S Manual

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Chapter 9. Managing GFS 107
By using the
gettune
action flag of the
gfs_tool
command, all current tunable parameters includ-
ing
atime_quantum
(default is 3600 seconds) are displayed.
The
gfs_tool settune
command is used to change the
atime_quantum
parameter value. It must
be set on each node and each time the file system is mounted. (The setting is not persistent across
unmounts.)
9.9.2.1. Usage
Displaying Tunable Parameters
gfs_tool gettune MountPoint
MountPoint
Specifies the directory where the GFS file system is mounted.
Changing the
atime_quantum
Parameter Value
gfs_tool settune MountPoint atime_quantum Seconds
MountPoint
Specifies the directory where the GFS file system is mounted.
Seconds
Specifies the update period in seconds.
9.9.2.2. Examples
In this example, all GFS tunable parameters for the file system on the mount point
/gfs1
are dis-
played.
gfs_tool gettune /gfs1
In this example, the
atime
update period is set to once a day (86,400 seconds) for the GFS file system
on mount point
/gfs1
.
gfs_tool settune /gfs1 atime_quantum 86400
9.10. Suspending Activity on a File System
All write activity to a file system can be suspended for a time by using the
gfs_tool
command’s
freeze
action. The
unfreeze
action returns the file system to its ordinary state. That feature allows
hardware-based device snapshots to be used to capture the file system in a consistent state.