CPU Time

From Unofficial BOINC Wiki

[edit] General

The use of the Central Processing Unit CPU of a computer is managed by an Operating System (OS) and the only way that the OS can do that is if it has a means of tracking the actual usage of the CPU by a Process (under the covers your program, such as a word processor, may be comprised of one or more processes and these processes may be composed of one or more Threads) over time. Once we start doing that we also can log those expenditures and provide (if desired or necessary) accounting for the use of the CPU by the programs running on the system. In the case of the BOINC Client Software we are not so much interested in the billing for the time expended as we are in tracking how much time is used overall for tracing purposes.

Note that the CPU Time required to process a Work Unit is based on the actual time expended by the CPU; it is often misunderstood that if you have a dual processor machine that you should divide the time expended by two. This is not correct. The CPU Time expended by each "Logical Processor" (in machines equipped with a Hyper-Threading CPU) or Physical Processor (in the case of a computer with two or more CPU chips) is still, say, 3 hours per Work Unit. The system throughput is one Work Unit each hour and a half expended of wall clock time.

One of the interesting possibilities for the use of computers in a Distributed Computing environment is that it may be come possible for the private individual to "rent" his spare computing time to a pay-for-use where you will become very interested in the amount of time expended because that will drive your reward.