Gfs Directory Attribute; Data Journaling - Red Hat GFS 6.0 Administrator's Manual

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9.7.2.2. Example
In this example, the command sets the
.
/gfs1/
gfs_tool setflag directio /gfs1/datafile

9.7.3. GFS Directory Attribute

The command can be used to assign a direct I/O attribute flag,
gfs_tool
GFS directory. Enabling the
files in that directory to automatically inherit the
is inherited by any new subdirectories created in the directory. The
be cleared.
9.7.3.1. Usage
Setting the
inherit_directio
gfs_tool setflag
Setting the
inherit_directio
gfs_tool clearflag
Directory
Specifies the directory where the
9.7.3.2. Example
In this example, the command sets the
.
/gfs1/data/
gfs_tool setflag inherit_directio /gfs1/data/

9.8. Data Journaling

Ordinarily, GFS writes only metadata to its journal. File contents are subsequently written to disk by
the kernel's periodic sync that flushes file system buffers. An
data to be written to disk immediately. The call returns when the disk reports that all data is safely
written.
Data journaling can result in a reduced
is written to the journal in addition to the metadata. An
to the journal, which can be substantially faster than the time it takes to write the file data to the main
file system.
Applications that rely on
journaling. Data journaling can be enabled automatically for any GFS files created in a flagged direc-
inherit_directio
flag
Directory
inherit_directio
flag
inherit_directio
inherit_directio
fsync()
to sync file data may see improved performance by using data
fsync()
flag on the file named
directio
flag on a directory causes all newly created regular
flag. Also, the
directio
Directory
flag is set.
inherit_directio
fsync()
time, especially for small files, because the file data
fsync()
Chapter 9. Managing GFS
datafile
inherit_directio
inherit_directio
inherit_directio
flag on the directory named
call on a file causes the file's
returns as soon as the data is written
in directory
, to a
flag
flag can also