  We present results of the implementation of one MILC lattice QCD
application-simulation with dynamical clover fermions using the
hybrid-molecular dynamics R algorithm-on the Cell Broadband Engine processor.
Fifty-four individual computational kernels responsible for 98.8% of the
overall execution time were ported to the Cell's Synergistic Processing
Elements (SPEs). The remaining application framework, including MPI-based
distributed code execution, was left to the Cell's PowerPC processor. We
observe that we only infrequently achieve more than 10 GFLOPS with any of the
kernels, which is just over 4% of the Cell's peak performance. At the same
time, many of the kernels are sustaining a bandwidth close to 20 GB/s, which is
78% of the Cell's peak. This indicates that the application performance is
limited by the bandwidth between the main memory and the SPEs. In spite of this
limitation, speedups of 8.7x (for 8x8x16x16 lattice) and 9.6x (for 16x16x16x16
lattice) were achieved when comparing a 3.2 GHz Cell processor to a single core
of a 2.33 GHz Intel Xeon processor. When comparing the code scaled up to
execute on a dual-Cell blade and a quad-core dual-chip Intel Xeon blade, the
speedups are 1.5x (8x8x16x16 lattice) and 4.1x (16x16x16x16 lattice).
