最近,我一直试图使用MySQL监控performance_schema服务器。以前,我通过使用cron作业每5秒运行一次显示完整PROCESSLIST查询来完成这一任务。我按照以下方式配置了performance_schema.setup_consumers表。mysql> use performance_schema;+-------------------------------
根据文档的说法:and has minimal impact on server performanceThe other
sources have negative performance consequences because they require a mutex.有一个标志,即performance_schema_max_sql_text_length,它控制为SQL查询分配了多少字节。
在生产服务器MariaDB 10.2.13上,我激活了插件query_cache_info。在每天批处理转储(使用mysqldump)的过程中,我突然出现了以下错误:
mysqldump: Couldn't execute 'SELECT /*!40001 SQL_NO_CACHE */ * FROM `QUERY_CACHE_INFO`': Character set '#4294967295' is not a compiled character set and is not specified in the '/usr/share/mys