I think that the copyHistograms step makes the files that enter the hadd stage fairly small, which allows to increase the number of inputs per hadd job significantly. At the moment, the hadd stage generates too many jobs each of which consume a mere 250MB of memory, while the mem cap is at 2GB.
I think that the
copyHistogramsstep makes the files that enter the hadd stage fairly small, which allows to increase the number of inputs per hadd job significantly. At the moment, the hadd stage generates too many jobs each of which consume a mere 250MB of memory, while the mem cap is at 2GB.