Tip

Cache maintenance key to server performance

Most administrators tend to set up a file system's cache and then forget about it. However, you can squeeze better performance from your server if you optimize your cache from time to time. You should check your cache to see if it still contains the file systems you want. If not, you might want to modify or recreate the cache. In Solaris, for example, there are several commands that let you display cache information, check a cache's consistency, check a file system's integrity, and delete or add file systems to the cache.

Assuming that you are using the /etc/vfstafb file to mount file system, in order to edit the file systems you would edit the entries for those file systems in the vfstab file. When you are using the AutoFS function, you can change file system options for the cache as part of the AutoFS amps. To specify a cache file system in the AutoFS map you need to add a line to the auto_direct map as a superuser.

Several commands are useful in your work of maintaining your file-system cache. The cfsadmin command will display information about the cache and its file systems, as well as allowing you to delete a file system from a particular cache. The cachefsstat command will show you statistical information about a file system, displaying information contained in the cache itself. The cachefspack command lets you specify which files and directories to pack into the cache.

If you suspect you have an integrity problem with your cache, you can check

    Requires Free Membership to View

the integrity and perform repairs using the fsck –F cache {-m} {-o noclean} cache_directory command.

Use the cachefswssize to determine if the log file's data suggests that you alter the cache size. You can also use the cachefslog command to view what is being logged to the cache log file, and to suspend logging, if desired. If you suspect that poor log performance is an issue, you can use the cachefslog command to move the log file to a faster disk or one with more available space.


Barrie Sosinsky is president of consulting company Sosinsky and Associates (Medfield MA). He has written extensively on a variety of computer topics. His company specializes in custom software (database and Web related), training and technical documentation.


This was first published in February 2003

There are Comments. Add yours.

 
TIP: Want to include a code block in your comment? Use <pre> or <code> tags around the desired text. Ex: <code>insert code</code>

REGISTER or login:

Forgot Password?
By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy
Sort by: OldestNewest

Forgot Password?

No problem! Submit your e-mail address below. We'll send you an email containing your password.

Your password has been sent to:

Disclaimer: Our Tips Exchange is a forum for you to share technical advice and expertise with your peers and to learn from other enterprise IT professionals. TechTarget provides the infrastructure to facilitate this sharing of information. However, we cannot guarantee the accuracy or validity of the material submitted. You agree that your use of the Ask The Expert services and your reliance on any questions, answers, information or other materials received through this Web site is at your own risk.