When the MoveInstances command is processed in the JCF
A file split operation that entails moving instances of several classes to at most one other target file is processed as a single task in one pass of the source file. You can process multiple file split tasks for different source files concurrently, using the specified number of worker threads.
When classes are remapped from a source file to more than one target file, each file split is processed as a separate task. Move operations are executed in batches or work units comprising one or more file split tasks. More than one work unit is required when the moves from a specified source file cannot be accomplished in a single pass of that file.
Each work unit is executed within a single atomic transaction that commits (or aborts) the reorganization and instantiation of database files as well as associated schema metadata updates.
Information (including errors) about the MoveInstances operation is written to the move.log file in the location specified by the