Update for
cpu family : 6
model : 26
model name : Genuine Intel(R) CPU 000 @ 3.20GHz
stepping : 4
Machine has 4 cores, each with 2 hyperthreads. /proc/cpuinfo shows 8 virtual processors.without -4way, setgen 4: 5.7 Mhash/sec without -4way, setgen 8: 5.0 Mhash/sec
with -4way, setgen 4: 7.0 Mhash/sec with -4way, setgen 8: 9.3 Mhash/sec
So, the old wisdom of “hyperthreading slows things down” is now shattered, on this machine.