mysql - PHP提示PDO failed
有一台MySQL服务器，每天上面都会新增数十个新数据库（三十 or 四十），截止到现在，已经有接近三千个数据库。单个数据库的访问量不大，但可能由于数量过多，最近经常性出现 PDO failed （Discuz的DB模块）错误。查看mysql错误日志又没发现什么有用提示。
想问问，出现类似这样的问题，应该从哪些方面考虑找原因？
下面列出的是部分 my.cnf 内容
<code>key_buffer_size = 32M max_allowed_packet = 2M table_open_cache = 256 sort_buffer_size = 6M net_buffer_length = 8K read_buffer_size = 2M read_rnd_buffer_size = 2M myisam_sort_buffer_size = 4M myisam_max_sort_file_size = 32M myisam_max_extra_sort_file_size = 32M query_cache_size = 128M thread_cache_size = 128 max_connections=256 tmp_table_size = 100M join_buffer_size = 8M </code>
回复内容：
有一台MySQL服务器，每天上面都会新增数十个新数据库（三十 or 四十），截止到现在，已经有接近三千个数据库。单个数据库的访问量不大，但可能由于数量过多，最近经常性出现 PDO failed （Discuz的DB模块）错误。查看mysql错误日志又没发现什么有用提示。
想问问，出现类似这样的问题，应该从哪些方面考虑找原因？
下面列出的是部分 my.cnf 内容
<code>key_buffer_size = 32M max_allowed_packet = 2M table_open_cache = 256 sort_buffer_size = 6M net_buffer_length = 8K read_buffer_size = 2M read_rnd_buffer_size = 2M myisam_sort_buffer_size = 4M myisam_max_sort_file_size = 32M myisam_max_extra_sort_file_size = 32M query_cache_size = 128M thread_cache_size = 128 max_connections=256 tmp_table_size = 100M join_buffer_size = 8M </code>
数据库索引改成innodb的?
不过三千个数据库,各种size才几兆几十兆,似乎配置太低了
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