[MEM_LIMIT_EXCEEDED]Process has no memory available, cancel top memory usage query: query memory tracker <Query#Id=17e36f4b1a154dd1-bc4d84f00f71ef38> consumption 2.24 MB, backend 172.21.145.181 process memory used 7.44 GB exceed limit 12.34 GB or sys mem available 1.42 GB less than low water mark 1.54 GB. Execute again after enough memory, details see be.INFO
这个错误怎么解决，测试环境由于内存只有16g，运行了有1年了报这个问题
