I found that setting the the VM parameter -Xmx , maximum size, to be a critical setting. A value about half the size of total memory has been working. The parameter can be changed in Options>Performance tab, or be edited the configuration file with a text editor. -Xms , minimum size, may be small (256M). Also useful to set the cache size, the medium value of the benchmark tests seems to work better than the smaller, default, value.