More information available here: http://wiki.blazegraph.com
It would be a good idea to review the RWStore.properties file.
It can be specified via java system properties via: -Dcom.bigdata.rdf.sail.webapp.ConfigParams.propertyFile=FILE
where FILE is the fully qualified path of the bigdata property file.
As written in the blazedgraph wiki: You should specify JAVA_OPTS with at least the following properties. The guidelines for the maximum java heap size are no more than 1/2 of the available RAM. Heap sizes of 2G to 8G are good recommended to avoid long GC pauses. Larger heaps are possible with the G1 collector (in Java 7).
export JAVA_OPTS="-server -Xmx2g"