Veritas Storage Foundation 5.1 SP1 Advanced Features Administrator"s Guide (5900-1503, April 2011)

To enable Concurrent I/O on a DB2 tablespace when creating the tablespace

Use the db2 -v "create regular tablespace..." command with the no

file system caching option.

Set all other parameters according to your system requirements.

To enable Concurrent I/O on an existing DB2 tablespace

◆

Use the DB2 no file system caching option as follows:

# db2 -v "alter tablespace tablespace_name no file system caching"

where tablespace_name is the name of the tablespace for which you are

enabling Concurrent I/O.

To verify that Concurrent I/O has been set for a particular DB2 tablespace

Use the DB2 get snapshot option to check for Concurrent I/O.

# db2 -v "get snapshot for tablespaces on dbname"

where dbname is the database name.

Find the tablespace you want to check and look for the File system caching

attribute. If you see File system caching = No, then Concurrent I/O is

enabled.

Disabling Concurrent I/O for DB2

If you need to disable Concurrent I/O, use the DB2 file system caching option.

Note: If you used the namefs -o cio option with the mountcommand to mount a

directory to enable Concurrent I/O, make sure you remount without that option

as well. Also, if you follow the directions for enabling Concurrent I/O on an existing

SMS container, rename the directory back to the original name.

To disable Concurrent I/O on a DB2 tablespace

◆

Use the DB2 file system caching option as follows:

# db2 -v "alter tablespace tablespace_name file system caching"

where tablespace_name is the name of the tablespace for which you are

disabling Concurrent I/O.

Improving database performance with Veritas Concurrent I/O

Enabling and disabling Concurrent I/O

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