Reducing local disk space requirements

About disk space requirements for content distribution

ContentDirector has local disk space requirements that are related to the content distribution process. These requirements are dynamic depending on your content distribution practices. They are separate from installation disk space requirements.

What you need to know to estimate requirements

To estimate your local disk space requirements, you need to know:

The size of the largest job you need to run
Whether you plan to run jobs concurrently, because the disk space required is additive across jobs - storage for jobs does not overlap
Whether you are running CD optimized for filer - this reduces the amount of local disk space required by a factor of (1 x the size of the content being pushed)

Components of local disk space usage

There are three components of local disk space usage for content distribution:

Shadow: a copy of the content pushed the last time a job was successfully run
Assignment: content and header data for each job currently running.
The size of the assignment file is not the same as the size of the raw content. It depends on the following factors:
- The size and number of the source files. In general, many small files require more overhead than a few large files.
- For jobs that send only file deltas (changes), the number and scope of the changes made to the source file since the job was last run
- For jobs with compression enabled, the level of compression
Temporary directory: temporary copy of content for each job currently running

You can relocate or eliminate all three of these components.

Approximate ratios for estimating space requirements

Local disk space requirements fluctuate with the cycle of job processing. The peak is for a job that has already been run at least once, and is just starting to run again. At that time, the maximum local disk space used is:

approximately four times the size of the content being pushed, if you implement no space-saving measures
approximately the same as the size of the content being pushed, if you implement all space-saving measures

These ratios apply to all jobs, regardless of size.

Keep in mind that the actual space required depends on what is being added, changed, or deleted by a particular distribution event.

Strategies for reducing local disk space needs

There are three strategies for reducing local disk space needs:

Move the shadow and temporary directories to a different drive by moving the workspace
Eliminate the shadow directory entirely by using an optimized filer for the content source
Move the assignment directory to a different drive

Move the workspace

The workspace contains the shadow directory and temporary directories. If you log onto ContentDirector as a system administrator, you can move the workspace either as a global preference or for each job. For details see Setting content distribution preferences and Creating jobs.

Use an optimized filer for content source

You can eliminate the shadow directory by locating the content source on an optimized filer. ContentDirector integrates with DataONTAP and uses snapshots for content backup, instead of the shadow. For details see Creating sources and Appendix E, Mapped Drive Permissions.

Relocating the assignment file

ContentDirector builds a temporary assignment file before running each job. The assignment file contains all the content and header information for the job. The default location for this file is under the install directory, in \ContentDirector\Ccm\jakarta-tomcat\webapps\ContentDirector\Assignments.

The assignment directory is different from the workspace, and its location is not affected by your choice of workspace.

To relocate the assignment directory, complete the following steps:

Caution
Caution: Do not make any other changes to these files other than the ones listed below. Be sure to use the correct case, as properties files are case-sensitive.

Step

Action

1
Stop the ContentDirector services.

2
Make backup copies of the files:

ContentDirector\Ccm\config\cm.properties
ContentDirector\jakarta-tomcat\conf\server.xml

3
Edit the file ContentDirector\Ccm\config\cm.properties.

4
Set the "cm_webserver_dir" parameter to the "root" of the new location, for example, for directory "z:/":

cm_webserver_dir=z:/

Note
For each job, ContentDirector creates a subdirectory under this root location named after the internal jobID. For example, for job 5005, the workspace is z:/5005

5
Save and close cm.properties.

6
Edit the file ContentDirector\jakarta-tomcat\conf\server.xml.

7
Add a new alias for ContentDirector, for example:

<Context path="/ContentDirector" docBase="z:/ContentDirector" debug="0" reloadable="true">

</Context>

8
Save and close server.xml.

9
Restart ContentDirector services.

Step	Action
1	Stop the ContentDirector services.
2	Make backup copies of the files: ContentDirector\Ccm\config\cm.properties ContentDirector\jakarta-tomcat\conf\server.xml
3	Edit the file ContentDirector\Ccm\config\cm.properties.
4	Set the "cm_webserver_dir" parameter to the "root" of the new location, for example, for directory "z:/": cm_webserver_dir=z:/ Note For each job, ContentDirector creates a subdirectory under this root location named after the internal jobID. For example, for job 5005, the workspace is z:/5005
5	Save and close cm.properties.
6	Edit the file ContentDirector\jakarta-tomcat\conf\server.xml.
7	Add a new alias for ContentDirector, for example: <Context path="/ContentDirector" docBase="z:/ContentDirector" debug="0" reloadable="true"> </Context>
8	Save and close server.xml.
9	Restart ContentDirector services.