Disk Usage in IDOL

See AlsoIDOL Internal Storage and Indexes

You can see the amount of disk space that IDOL uses by using the DiskReport action. Alternatively, you can view information about the disk usage of directories and files in the working directory for each component on the Disk Report tab of the Performance page in the Monitor section of IDOL Admin.

The following sections describe how to reduce disk usage for particular indexes.


You can dramatically reduce the amount of disk space required by the nodetable if there are any fields in the document that you do not actually need to store for retrieval.

If you retrieve the documents from a different system by using the reference, you can configure IDOL to index the body of the document (usually extracted as the DRECONTENT field) but not store it. In this case, operations that require the original document body (for example, highlighting, and the GetContent action) require additional processing by the application that uses IDOL. For example, rather than sending a GetContent action to IDOL Server, it must request the document from the original repository, or through a Connector.

The KeyView extraction process might pull out fields or information that your particular IDOL system does not require. In this case you can also discard these fields and not store them.

There are two mechanisms for discarding fields:

Some functionality is unavailable for non-stored content, but in some cases there are alternative methods that you can use. For more information, see Storage of Document Content.

Storing fields allows IDOL to retrieve the data without needing to go back to the document source, and can improve overall query performance. You can also regenerate stored fields if index validation fails, or if you need to change the field configuration after indexing.

You can use the NodeTableCompression configuration parameter to compress the documents in the nodetable on disk. In this case, IDOL Server compresses data in the nodetable directory before storing it, reducing the IDOL Server disk footprint.

Index Cache, Diskindex and Unstemmed

The main methods for reducing disk usage of these indexes attempt to reduce the amount of indexed data.These methods include:

Reducing the TermSize also reduces the disk usage for the diskindex and index cache, but normally this gain is minimal.

Reducing TermSize by 1 for an index with 1 million unique terms only reduces disk space usage by 1 MB.

You can further reduce the unstemmed disk space usage by using the UnstemmedIndexNumbers and UnstemmedMinDocOccs configuration options.

The AdvancedPlus option can contribute to the disk usage of the diskindex. To minimize the diskindex size, Micro Focus recommends that you turn this option off unless you particularly need the SENTENCE and PARAGRAPH matching.

Other Indexes

For the Match, Numeric, and Parametric indexes, you can reduce disk usage only by limiting the amount of data indexed for those types.

For the Sort index, you can reduce disk usage by limiting the SortFieldStorageLength parameter.