redhatlinux
Senior member
Applications are NOT dual core per se. They have to written as multi-threaded, just to get the terminology correct. Some applications are easily converted to multi-threading, others are not. As a general rule of thumb from multi-processors back in the main frame days. Two processors give about 1.6 to 1.7 times the throughput of a single processor, providing the i/o is capable of 'feeding' the second cpu. I effectively split a dual cpu mainframe into 2 singles, each with plenty of i/o and pretty much got the equivalent of 2 cpu's. This is a rare condition. Look for an architecture with the highest i/o throughput to gain the most. (read AMD hyper-transport). Signal processor traffic can slow down the entire system by about 10% if its heavy enough. BTW Hitachi made a 4 cpu system and the performance was pretty poor. The OS spends too much time with the 'balls in the air', instead of actually processing applications. Scientific apps with massive arrays of data get closer to 1.8 - 1.9 the single processor speeds.