An efficient search key processing method includes writing a first and a second search key data set to a memory, where the search key data sets are written to memory on a word by word basis. Each of the first and second search key data sets includes a header indicating a common lookup operation to be performed and a string of search keys. The header is immediately followed in memory by a search key. The search keys are located contiguously in the memory. At least one word contains search keys from the first and second search key data sets. The memory is read word by word. A first plurality of lookup command messages are sent based on the search keys included in the first search key data set. A second plurality of lookup command messages are sent based on the search keys included in the second search key data set.