Xsan 1.2: Modify the JournalSize parameter on upgraded Xsan installations for improved performance

In Xsan 1.2, the default value for a volume's JournalSize parameter has been increased from 4 MB to 16 MB. Increasing this value improves the performance on installations with intensive metadata loads, such as for home directory usage and general purpose file servers.

Because the new default value is written to a volume's config file at the time of creation, you must manually edit the config file for existing Xsan installations that you've upgraded to version 1.2 to get the performance benefit.

To change the JournalSize value for a volume:

1. Using Xsan Admin, stop the volume that you want to modify.
   Note: You don't need to unmount the clients.
   
   
2. Open the file /Library/Filesystems/Xsan/config/volumename.cfg in the editor of your choice.
   
   
3. Locate the JournalSize parameter, and change the value from 4M to 16M.
   Note: If you have more than one metadata controller (MDC), make sure to modify the volume config file on all of them.
   
   
4. On an MDC, execute this command:

   sudo cvupdatefs volumename

   
   Note: If you have more than one MDC, you don't need to run this command on each of them—just on one.
   
   
5. Using Xsan Admin, start the volume.

Clients should be able to access the volume as before.

Related articles

• 301639: Xsan 1.1—Modify upgraded Xsan installations for increased performance and stability