High utilization when multiple Macintosh workstations mount home directories

  • 7001883
  • 14-Nov-2008
  • 26-Apr-2012

Environment

Novell NetWare 6.5
Macintosh OS X

Situation

High utilization on the server.

Caused by a combination of things:
- The MAC AFP protocol requests rights information about every item in a directory / often it will ask several times.
- Thousands of Home Directories in a Users directory on a volume.
- Hundreds of students logging in at the same time mounting their home directories
- AFP on NetWare is single processor enabled.  (Mutliprocessor enableing AFP might help somewhat but the real problem is the unusually large volume of requests generated by this protocol.)
 
NetWare has no problems handling this number or more Home Directories in a single directory when accessed through CIFS or NCP.
 
The problem isn't NetWare scalability.
 
The problem is the enormous amount of traffic generated by the MAC workstations.  Each workstation will find out how many items are in the parent directory containing the students home directories and then ask for their inidividual rights to each item in that directory.  This usually happens several times for each item.  When the whole list is processed the workstation will then display or mount the one directory it was looking for.
 
In a school environment where hundreds of students access their home directories all at the same time at the beginning of class, if all of the students home directories are all in the same folder, the MAC workstations will generate MILLIONS of requests (REALLY!) for rights information before performing the simple task of displaying or mounting the users home directories.
 
The server will go into higher than normal utilization until it is able to finish processing this tidal wave of requests.

Resolution

The fix for the high utilization is to subdivide the users directories into smaller groups.  You can divide them by grades, classes, or even alphabetically so that when the workstation goes to the directory where the users home directory resides the workstation has less folders to generate rights requests for before accessing the one it needs.

While this can be done by hand, Novell has a product on the price list called Novell Storage Manager (Formerly File System Factory) that was designed to automate the management of home directories.  This product was designed with the academic community in mind.  Here is a link to the product page which contains an eval download and information about this solution.  https://www.novell.com/products/storagemanager/

Additional Information

Formerly known as TID# 10097049