General Topics :
Work Unit of 80+ hours??
Posted 14 Oct 2011 by mickydl*
3.33 days is only true if you run the machine 24/7. Although many of us do , some don't.
My machines are switched off during the night and are running an average of 15 hours a day.
Another thing I have encountered during one of the last WUs I crunched is that the checkpointing seems to be quite inefficient. The particular WU had finished to abt. 80% when I switched the machine off for the night. When I started everything on the next day it continued from it's last checkpoint at 60% (corresponding to several hours of work). I didn't investigate this any further so I don't know if this is the normal behavior or just an unlucky coincidence.
So, let's make a new calculation :-)
80 hours / 15 hours per day = 5.33 days
add 5 % penalty (maybe 10% ?) for checkpointing and you get 5.6 days (5.68).
If at least one other project is being crunched on the same machine double the times. So now we have 11.2 days (or 11.73 days with 10% penalty).
OK, it's still less then the 15 day deadline but we are getting closer. Add yet another project to BOINC on that machine and you're likely to run into the "high priority" problem.