What causes Database Optimization to take a long time to complete, with an Oracle Database?
Whenever FTK is inserting data into the database, Oracle by default tries to update the bit-map indexes on the fly. However since FTK is not trying to query the data during the time it is processing, it is in-efficient to allow Oracle to try to make these updates and in makes the processing of the evidence take much longer than needed. In an effort to increase evidence processing speed and lower time to completion of the evidence processing, FTK tells Oracle to turn off bit-map indexing at the commencement of every job submitted to the processing engine. After the processing of the evidence is complete, FTK instructs Oracle to resume bit-map indexing known as "Database Optimization". Users experiencing a long delay in the completion of Database Optimization should note the following:
- Three of the main tasks performed by Oracle during Database Optimization are:
- Build or rebuild bit-map indexes
- Flag duplicate files
- File list export
- It is important to note that the time required to complete Database Optimization will increase proportionate to:
- The number of file items in a case needed to be examined in order to build or rebuild bit-map indexes.
- A lack of memory available to Oracle
- A lack of disk I/O available to Oracle
- The number of files to be checked "Flag Duplicates" is enabled
- The number of files in the case to be included in the "File List Export" if enabled.
- To solve this issue a user should:
- Use 64 bit architecture
- Increase the physical memory to at least 8 GB of RAM
- Only select the processing options appropriate for the investigation and avoid "Flag Duplicates" and "File List Export" during pre-processing. Both of these options can be run after the case has completed processing.
- Install Oracle to a drive or set of drives with a high rate of disk I/O (See FTK 3 system spec guide)