public Builder vmCount(int vmCount) {
      this.vmCount = vmCount;
      return this;
    }
Specifies the number of DUnit VMs to startup.

@param vmCount the number of DUnit VMs to startup
@return a reference to this Builder
geode-dunit/src/main/java/org/apache/geode/test/dunit/rules/DistributedExecutorServiceRule.java