AMD introduced HT Assist as a feature on the new Six-Core AMD Opteron™ processor. HT Assist can boost overall system performance on 4P and 8P servers by up to 60% in some applications by reducing many common CPU-to-CPU transactions. It does this by creating a lookup table that allows each CPU to know exactly where needed data lies within other CPUs in the configuration, thus reducing probes and eliminating the need to “broadcast”, or probe each CPU independently.
NOTE: While the HT Assist feature is available on all 24xx and 84xx series models, AMD does not recommend using the feature in 2P configurations. HT Assist requires 1MB of L3 cache per CPU to operate, and the benefit of the probe filter traffic reduction is negated in most 2P situations, unlike 4P configurations, which experience a higher rate of probe filter traffic.