Blockchain is a technical solution to jointly maintain a reliable database in a decentralized and trustless way. Since the birth of blockchain technology, the performance of blockchain has always been a key issue that has attracted much attention and discussion. Therefore, a performance testing tool can help evaluate the performance of different blockchain systems and guide further optimization. This paper proposes xBCBench, a benchmarking tool for analyzing the performance of blockchain systems, which can be used to compare the performance of different blockchain systems. xBCBench evaluates the performance of blockchain systems based on the metrics like throughput, latency, and system resource utilization. We also use xBCBench to analyze four mainstream blockchain systems (i.e., Ethereum, Hyperledger Fabric, Hyperledger Sawtooth and FISCO-BCOS) and propose further optimization suggestions.