Hi, Recently, we upgrade 8 MariaDB slaves from MariaDB 10.1.22 to MariaDB 10.2.6. In error log, it frequent occurrence some innodb Note: ............. 2017-06-26 9:01:03 140022654363392 [Note] InnoDB: page_cleaner: 1000ms intended loop took 6142ms. The settings might not be optimal. (flushed=16 and evicted =0, during the time.) 2017-06-26 9:03:54 140022654363392 [Note] InnoDB: page_cleaner: 1000ms intended loop took 4584ms. The settings might not be optimal. (flushed=8 and evicted= 0, during the time.) 2017-06-26 9:05:58 140022654363392 [Note] InnoDB: page_cleaner: 1000ms intended loop took 4728ms. The settings might not be optimal. (flushed=8 and evicted= 0, during the time.) 2017-06-26 9:08:49 140022654363392 [Note] InnoDB: page_cleaner: 1000ms intended loop took 5016ms. The settings might not be optimal. (flushed=8 and evicted= 0, during the time.) 2017-06-26 9:09:12 140022654363392 [Note] InnoDB: page_cleaner: 1000ms intended loop took 4990ms. The settings might not be optimal. (flushed=8 and evicted= 0, during the time.) 2017-06-26 9:11:27 140022654363392 [Note] InnoDB: page_cleaner: 1000ms intended loop took 5387ms. The settings might not be optimal. (flushed=8 and evicted= 0, during the time.) 2017-06-26 9:14:43 140022654363392 [Note] InnoDB: page_cleaner: 1000ms intended loop took 6463ms. The settings might not be optimal. (flushed=0 and evicted= 0, during the time.) 2017-06-26 9:16:27 140022654363392 [Note] InnoDB: page_cleaner: 1000ms intended loop took 4031ms. The settings might not be optimal. (flushed=40 and evicted =0, during the time.) ............ Now, It have not affect the normal use, but we could not confirm, it is our config problem or other reasons? Please help confirm, thanks.