Linux supports transparent huge page since 2.6.38. It can automatically map huge pages. But this implementation fails to adjust to page alignment in memory allocation and thus cannot use huge page in some situations. The design is not efficient. Our work aims to increase huge page allocation, so as to improve the utilization ratio of huge page and overall performance. The experimental results show that the optimization almost reaches the upper bound of huge page utilization. This software approach delivers a notable performance improvement for a few benchmarks with moderate overhead in physical memory consumption.