Compression scheme with control of search agent activity

In connection with compression of an input stream, multiple portions of the input stream are searched against previously received portions of the input stream to find any matches of character strings in the previously received portions of the input stream. In some cases, matches of longer character strings, as opposed to shorter character strings, can be selected for inclusion in an encoded stream that is to be compressed. Delayed selection can occur whereby among multiple matches, a match that is longer can be selected for inclusion in the encoded stream and non-selected a character string match is reverted to a literal. A search engine that is searching an input stream to identify a repeat pattern of characters can cease to search for characters that were included in the selected character string match.