Quantum 3.1.3 User Manual

Chapter 6  Managing the File System

Working With Stripe Groups

StorNext User’s Guide

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After the status screen indicates that the disk has been deleted, click 

Close.

6

This procedure describes how to defragment a disk using the 
snfsdefrag

 utility to relocate SNFS file data into a single, pre-allocated 

extent. Reducing the number of extents in a file improves system 

performance by minimizing disk head movement when I/O occurs. You 

can defragment a single file or multiple files, perform a recursive 

defragment on files in a directory, or defragment the entire file system.

Log onto a metadata controller as root. The metadata controller is the 

computer where the StorNext server (not the client) is installed.

Do one of the following:
• To defragment a single file or a list of files, type:

/usr/cvfs/bin/snfsdefrag <filename> [filename ....]

• To perform a recursive defragment on files in a directory, type:

/usr/cvfs/bin/snfsdefrag -r <directory_name>

If the directory_name value is equal to the mount point, then the 

entire StorNext file system is defragmented.

Working With Stripe Groups

A stripe group is a logical disk volume in a file system that consists of one 

or more LUNs used to store metadata information, journaling 

information, and user data. Stripe groups are used to create logical 

volumes that can span multiple controllers on an array and even multiple 

arrays for even greater performance. Stripe groups are composed of 

LUNs of the same size and disk class based on your cost and performance 

requirements. (Fibre channel provides the highest performance and duty 

cycle.)

For more information about using the snfsdefrag 

command, refer to the snfsdefrag(1) man pages.