In this section we present examples of how Carnival can be used to tune applications running on Treadmarks. All experiments were performed on a cluster of eight DEC Alpha Server 2100 nodes connected by a DEC Memory Channel [5]. Each Alpha Server node has four 233 MHz Alpha processors with 256 Mb of memory. Applications are linked to an instrumented implementation of Treadmarks (version 0.9.6), which employs DEC's implementation of TCP/IP on the Memory Channel.