![]() My memory suggests that there was more detail in an email - perhaps on the development or projects email lists - around that time: I'll have another look now that I have an exact date. ![]() This is the evidence which is hard to track down, but I found a smoking gun in SVN revision 21962 of Jul 15, 2010. But in the summer of 2010, it was adjudged that a mistake had been made, and the true definition should have used 200 all along. How did the documentation discrepancies come about, I hear you ask? When BOINC and this web site was first set up, the original figure was 100, and this will have been copied into the earliest sources. Similarly, the BOINCstats page I linked is showingĪverage floating point operations per second 20,880,857.3 GigaFLOPS / 20,880.857 TeraFLOPSIt's no coincidence that the first figure is exactly 200 (less several orders of magnitude) larger than the second figure - fpops is calculated from credit, not the other way round. $petaflops = number_format($credit_day/200000000, 3) - which is where the magic 200 that you're trying to track down can be found. The source code for this web site is at : I think BOINCstats archives a wider range of data from more projects than this site does. The value today is stated as 14.879 PetaFLOPS (this site), or 20,880.857 TeraFLOPS (BOINCstats). A number of places - most notably, the home page of this web site, but also a number of the statistics sites like - will quote you the total processing power of the BOINC platform, or a subset of it like a single project. ![]() The second version is actually easier to track down an authoritative source for. "How many Fpop-days did I compute in order to earn 1 BOINC credit?" Answer = 1/200 "How many credits should I get for a day's processing on a 1 GFLOP device?" Answer = 200 Your second statement is the one officially recognised by BOINC:ġ BOINC credit equals 1/200 day CPU time 1 GFLOPs/secondThere are two complementary calculations: Sorry, I could have answered this from memory yesterday, but it's proved hard to locate the documentary evidence that you have the right to request. There should be one single definition for the Cobblestone. ![]() I am just trying to save other people the confusion about a subject that is not trivial to understand by itself. Using an analogy: it is like defining the mile as 1,609.34 meters and also as 3,218.69 meters. And something should be done about it (please refer to the second set of 3 links I mentioned in my original post). If I am wrong, the documentation should be corrected in the first set of 3 links I mentioned in my original post.īut, if I am right, the documentation in the official BOINC Wiki and on the English Wikipedia article (the Spanish Wikipedia article use the other definition), are the ones that would be wrong. What I am trying to point out is that there is documentation online that define the exact same thing, the Cobblestone (BOINC credit), in 2 different ways:ġ) As 1/100 day CPU time 1 GFLOPs/second (I really think this is the right one)Ģ) As 1/200 day CPU time 1 GFLOPs/second I also undestand the difficulty to properly compare GFLOPS on different CPUs/GPUs/APUs architectures, models, generatios, and that many other variables can affect it. For example, that 7 World Community Grid credits equal to 1 BOINC credit (1 Cobblestone). I understand the fact that different BOINC projects may have different credit/GFLOP assignement values, it is actually one of the first things I noticed when trying to understand BOINC credit. Is it?Ĭan the we finally and correclty state that: Surprisingly, in some cases, sources with different definitions do refer to each other.Īfter much head scratching, and doing some calculations with the credits that my crunching devices got for the last month, I concluded that the first one is the right definition. Sources that state that 1 BOINC credit equals 1/200 day CPU time 1 GFLOPs/second Sources that state that 1 BOINC credit equals 1/100 day CPU time 1 GFLOPs/second ![]() I found 2 very different definitions for the BOINC credit: The goal was to try to identify the CPUs and GPUs with the best GFLOPS/price and GPLOPS/Watt relations, withing a certain budget, and having BOINC in mind. I ran over this when doing some research that would help me to take an informed decision regarding my future computer hardware upgrade. I have been running BOINC for almost 10 years now, and I had never bother to figure out exactly what a BOINC credit meant, I just knew more is better :) ![]()
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