The mapping task passes all incoming data into the Sorter transformation before it performs the sort operation. The mapping task uses cache memory to process Sorter transformations. If the mapping task cannot allocate enough memory, the mapping fails.
By default, the mapping task determines the cache size at run time. Before starting the sort operation, the mapping task allocates the amount of memory configured for the Sorter cache size.
Configure the Sorter cache size with a value less than the amount of available physical RAM on the machine that hosts the Secure Agent. Allocate at least 16 MB (16,777,216 bytes) of physical memory to sort data with a Sorter transformation. When you allocate memory to the Sorter cache, consider other transformations in the mapping and the volume of data in the mapping task.
If the amount of incoming data is greater than the Sorter cache size, the mapping task temporarily stores data in the work directory. When storing data in the Sorter transformation work directory, the mapping task requires disk space of at least twice the amount of incoming data.
When you configure the tracing level to Normal, the mapping task writes the memory amount that the Sorter transformation uses to the session log.