File Size Support

The support for file size now includes the following enhancements:

The following topics in Advanced Operations Guide provide additional details pertaining to these enhancements:

Maximum File Size of 128 Gigabytes

In previous releases, the maximum size of a data file was 64 GB. The maximum size is now 128 GB. A new file format supports the increased file sizes. You must use the Pervasive.SQL 9 file format to have a single file size larger than 64 GB. However, you do not need to rebuild a version 8.x file to use the increased limit.

File Segmentation

In previous releases, a data file was automatically broken into 2 GB operating system file segments as its size passed that boundary. Segmentation is now optional.

A new configuration property in Pervasive.SQL Control Center, "Limit Segment Size to 2 GB," allows you to specify whether you want files divided into 2 GB segments or unified in a single, non-segmented file. The advantage of using a larger non-segmented file size is more efficient disk I/O, which usually results in increased performance.

The configuration option is part of the Performance Tuning properties for a database engine. See To access configuration settings in PCC for an engine in Advanced Operations Guide.

The property is set to "Yes" by default, causing files to segment at 2 GB boundaries as with previous releases. If you set the property to "No," version 9 files can increase past the 2 GB boundary without being segmented. See also Automatic Upgrade of File Version for additional information relating to the configuration property.

Any non-segmented large files are still subject to the limit on file size specified by your operating system. If a previously created file is already segmented, that segmentation remains on the file.

Automatic Upgrade of File Version

If the configuration property "Create File Version" is set to 9 (the default), version 8.x files are automatically converted to version 9 files when they reach the file limits for version 8.x, which is 64 GB. The following table summarizes this behavior.

For example, a version 8.x file that is 5 GB in size has already passed the 2 GB segmentation boundary. Because the file is already segmented, the segmentation remains on the file. Such a file would continue to segment and grow in size until it reaches 64 GB, at which size the automatic upgrade would occur. This is true whether the configuration property is set to "yes" or "no" because the file is already segmented. As the file grows beyond 64 GB, it will continue to segment until it reaches the maximum size allowed for a version 9 file, 128 GB.

A version 8.x file that is 1.5 GB in size would continue to grow until it reaches 2 GB in size. At that point, the automatic upgrade occurs if the configuration property is set to "no." The file can continue to grow as a non-segmented file up to the size limit for version 9 files, 128 GB. If the configuration setting is set to "yes," the 2 GB file would continue to segment and grow until it reaches 64 GB in size. At that size, the maximum for a version 8.x file, the automatic upgrade to version 9 occurs. As the file grows beyond 64 GB, it will continue to segment until it reaches the maximum size allowed for a version 9 file, 128 GB.

The "Create File Version" option is part of the Compatibility properties for a database engine. See To access configuration settings in PCC for an engine in Advanced Operations Guide.