  We report results of autocorrelation measurements in pure $SU(3)$ lattice
gauge theory. The computations are performed on the {\sc convex spp1200}
parallel platform within the {\sc canopy} programming environment. The focus of
our analysis is on typical autocorrelation times and optimization of the mixing
ratio between overrelaxation and pseudo-heatbath sweeps for generating gauge
field configurations. We study second order tadpole-improved approximations of
the Wilson action in the gluon sector, which offers the advantage of working on
smaller lattices ($8^3~\times~16$ and $6^3~\times$~12~--~30). We also make use
of anisotropic lattices, with temporal lattice spacing smaller than the spatial
spacing, which prove useful for calculating noisy correlation functions with
large spatial lattice discretization (of the order of 0.4 fm).
