How do you decide how much credit a work unit is worth?
How do you determine how many points a work unit is worth? Before putting out any new work unit, we benchmark it on a dedicated 2.8GHz Pentium 4 machine with SSE2 disabled (more specifically, as reported by /proc/cpuinfo on linux: vendor_id : GenuineIntel, cpu family : 15, model : 2, model name : Intel® Pentium® 4 CPU 2.80GHz, stepping : 9, cpu MHz : 2806.438, cache size : 512 KB). This machine runs linux, so all WUs are benchmarked with the linux core.
We plug the results of this into the following formula:
points = 110 * (daysPerWU)
where daysPerWU is the number of days it took to complete the unit. This equation was chosen to match the points for previous Gromacs WUs to the previous point system. The upshot is that Tinker WUs will be worth more than before we set up the new points (i.e. before April 2004).
Please note that the very concept of a reference machine will mean that some WU benchmarking will vary from the performance on your machine. Even between P4s, there are significant differences in architectures over the years. Moreover, variations between FAH WUs can also lead to differences in benchmarking points.
Our goal is consistency within a given definition of a reference machine setup (described above), but beyond that the natural variation from machine to machine and WU to WU will never alllow any point system to perfectly reflect what you get on your machine.
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