PRIMECLUSTER Global File Services Configuration and Administration Guide 4.1 (Linux)

1.8.6 Notes of updatedb(1L)

Function to retrieve the location of the file at high speed is provided in Linux as locate(1L). To update the file name data base used for it, updatedb(1L) is regularly executed. Updatedb(1L) retrieves the file on each file system, and updates the file name data base.

The file access performance might become remarkably slow while updatedb(1L) is being executed at GFS Shared File System. To evade it, it is recommended to set up not to register the files on GFS Shared File System to the file name data base.

The file on the GFS Shared File System can not be retrieved by locate(1L) when setting up it.

So as not to register the files on the GFS Shared File System to the file name data base, add "sfcfs" to PRUNEFS parameter (specifies the file system excluded from the retrieval object by updatedb(1L)) defined in /etc/updatedb.conf. It must be set up on all nodes which share the GFS Shared File System. The following shows an example of setting.

    # cat /etc/updatedb.conf
    PRUNEFS="devpts NFS nfs afs proc smbfs autofs auto iso9660 sfcfs"
    PRUNEPATHS="/tmp /usr/tmp /var/tmp /afs /net" 
    export PRUNEFS
    export PRUNEPATHS

Unavoidably, when the files on the GFS Shared File System is registered to the file name data base, deterioration in the file access performance can be reduced while updatedb(1L) operates by setting as follows.

• Set the execution time of updatedb(1L) to when GFS Shared File System is accessed fewer according to the user operation.
• Adjust the execution time of updatedb(1L) to avoid executing updatedb(1L) simultaneously by the nodes which shared GFS Shared File System.

Usually, updatedb(1L) is executed by the file that exists on the /etc/cron.daily directory. So the execution time of updatedb(1L) can be changed by changing the execution time of /etc/cron.daily that is specified in /etc/crontab.

For details of the contents of /etc/crontab, see crontab(5).