Performance characteristics of multi-core and CMT servers

Multi-core and chip-level multi-threading systems face serious challenges related to performance scaling. Their performance is dominated by I/0 bus crossings, cache misses and interrupts. In this article we analyse the performance characteristics of typical server systems utilising Sun Niagara T1, Intel Pentium D and AMD Opteron CPUs. Based on our results, we conclude that highly parallel CMT systems, such as the Sun T2000, have the potential to significantly benefit from their architecture - as long as their computational resources are used appropriately. Some of this allocation can be left to the operating system, but some must be tuned by careful hand design of the software, pipelines and dependencies between hardware strands.