Paul D. Buck wrote > The problem is that Eric's script will mean that over a 4 year life of > a computer the CS it earns in year four will take more processing time > to obtain. That is the flaw ... as the performance average increases > the award goes down. So the CS I earned when I started BOINC 5-6 > years ago, what ever it was, took less processing power over time than > the same CS today (all other things being equal).
I'm not 100% sure, but I *think* that is a mis-reading of the purpose and behaviour of Eric's script. The script compares the credit awarded to the current cohort of machines under that project's active credit-scoring scheme (flop counting, in the case of SETI), with the credit that would be awarded to the *same* cohort of machines under the benchmark*time 'cobblestone' scheme. Then adjusts accordingly, with smoothing and median-taking to reduce the effect of outliers. So, Eric's script will *not* alter the value of the cobblestone over time merely because machines get, on average, faster: in principle, both flopcounts and benchmarks should increase in proportion. In practice, architectural changes and more efficient processor designs will mean that flopcounts increase more rapidly than benchmarks with technological advances (already evident in the different flop / benchmark ratios of Intel and AMD processors). So Paul's predicted behaviour is real, but it's a second-order effect and *not* an automatic, deliberate, design intention of the script. The other problem with the script is that will be thrown into total confusion if GPU processing ever approaches the median. At the time Eric wrote it, neither elapsed time nor GPU speed was available in the result table, so a _G_PU result would be compared against _C_PU time and _C_PU benchmark! Not pretty. I don't know of Eric has had time to consider how to include the (very new) recorded GPU metrics in the script, but it needs to be on the to-do list if the script is going to be considered for wider long-term use. _______________________________________________ boinc_dev mailing list [email protected] http://lists.ssl.berkeley.edu/mailman/listinfo/boinc_dev To unsubscribe, visit the above URL and (near bottom of page) enter your email address.
