We can separate TajoPullServer to another Java processor in order to mitigate the performance degradation caused by GC. TajoPullServer uses JAVA_PULLSERVER_HEAP_MAX to specify the max heap of TajoPullServer java processor. Currently, it is set to 100MB. It is somewhat smaller than usual size clusters. This patch changes the HEAP_MAP to 1000MB which seems to be proper in usual size clusters.