A content search system for determining whether a plurality of input strings each belonging to any one of a number of different process flows matches one or more of a plurality of regular expressions, including a search circuit for searching the input strings for the regular expressions and a data management unit including a control circuit having an input to receive the plurality of input strings, wherein each input string has an associated flow identification (ID) value, a packet queue having a number of storage locations for storing the input strings, and a flow engine that forwards a selected input string from the packet queue to the search circuit.