This attribute specifies the maximum number of codewords to be
used for compression. A codeword is a binary number that
represents a string of characters. Changes to this attribute impact the
amount of memory used (more memory is used when increasing the
attribute). The gain in performance obtained from the selection of a
larger dictionary may be offset by the larger codeword size needed,
and for certain types of data, better performance may be obtained
by using a smaller dictionary.
Changes to this attribute do not affect existing calls.