Published on 08-21-11 09:35 PM
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Cobblestones: The speed of the reference computer against which all computers participating in a BOINC project is measured. A reference computer would perform work to the credit equivalent of 100 cobblestones per day.
Credit: The number of cobblestones claimed or granted for completed Work Units (WU's) that successfully complete and are accepted by the project. First credit is claimed for a WU based on the amount of time it took. Then when validation occurs (see below) a possibly different credit is granted. The total claimed credit for which no credit has been granted is referred to as the Pending Credit.
Crunching: The processing of a downloaded WU using the projects application to look for whatever it is the the project is trying to do.
Recently Averaged Credit (RAC): This shows the measure of the rate at which your granted credit is growing If it goes up, you are accelerating, if it is dropping then either you or the others crunching the same WU's as you are slacking or the project is having validation problems and dropping behind.
Scheduling: This is the process of communicating with the client computer to tell it to tell it information from the central server. This includes both information on the current state of the users and teams statistics and what WU's to download when the client asks for some more.
Transitioning: The process of the projects servers examining a WU's state and deciding on what to do with it next. This can be to either send it out, pass it on for validation (enough matching results have been received) or send another copy out (as one/more of the existing ones have exceeded their return date or had errors returned. The most important to crunchers of these is the step of passing a WU for validation. On SETI@Home (and most other projects but not all) a WU is sent to three or more computers initially and when three have returned a result - and all three agree on the result then the result is transitioned for validation and credit is designed. Where there is a difference of opinion (for example one of them may have a hardware or overclocked problem and may return in invalid result or it may be running a beta version of a client) then additional copies are transitioned and sent out and the users who have already completed the WU wait for the additional results to be returned before it is considered for validation again.
Trickle: Some BOINC projects (e.g. CPDN) have very large WU's which often take several weeks to process. To inform the project that work is taking place and where you are up to - as well as return results and grant interim credit they implement the trickles every so often during the crunching of the WU. CPDN implements 72 trickles within its present WU's averaging about 6 trickles per day on a fast system.
Validation: The process of the projects servers granting credit for returned work. When three matching ones are found, then the Highest and lowest claimed credits are ignored and all three (or more) who return the result are granted the claimed credit of the middle one.
Work Units (WU's): The small segment of the overall program sent to the client computer to process and return as a result.