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System Administration Guide

How to Check File Access (sar)

Display file access operation statistics with the sar -a command. 


$ sar -a
SunOS venus 5.6 Generic sun4c 08/20/96
14:28:12    iget/s namei/s dirbk/s
14:29:12         0       2       1 
14:30:12         0       4       1 
14:31:12         0       3       1
Average          0       3       1

The operating system routines reported are described in Table 64-7.

Table 64-7 Output from the sar -a Command

Field Name 

Description 

iget/s

The number of requests made for inodes that were not in the directory name lookup cache (dnlc).

namei/s

This is the number of file system path searches per second. If namei does not find a directory name in the dnlc, it calls iget to get the inode for either a file or directory. Hence, most igets are the result of dnlc misses.

dirbk/s

This is the number of directory block reads issued per second. 

The larger the values reported, the more time the kernel is spending to access user files. The amount of time reflects how heavily programs and applications are using the file systems. The -a option is helpful for viewing how disk-dependent an application is.