在用tassel对vcf进行sort时报的错，有哪位大佬知道怎么操作吗

ERROR net.maizegenetics.plugindef.ThreadedPluginListener - Out of Memory: SortGenotypeFilePlugin could not complete task: Current Max Heap Size: 29809 Mb Use -Xmx option in start_tassel.pl or start_tassel.bat to increase heap size. Included with tassel standalone zip.