CPUID

From FaHWiki

There are 3 ID values:
1. MachineID;
2. UserID;
3. CPUID=UserID+MachineID;

To communicate with the FAH servers the FAH client must provide a valid CPUID value.
If the FAH client can not report a valid CPUID value then the FAH Assignment Server will give it an UserID value and this UserID value will get stored to the donator machine. But UserID itself is not a whole CPUID. To get the CPUID it has to add UserID and MachineID together. Now it has the proper CPUID to provide to the FAH servers.

MachineID identifies FAH client instances per computer. The donator MUST change the MachineID value if there is a need to run multiple copies of FAH client on THAT computer or the FAH servers will treat those multiple FAH clients as one and will assign the same WUs to all those clients.

Note: The same result (different CPUID value) can be achieved by changing UserID value, but that is not something the donator itself should ever do.

Finally, the FAH stats system is actually counting different CPUIDs, not active CPUs itself.

See also: the CPU ID field in the queue.dat file