The response of discuz posting is slow.

I use a cloud server, the website access speed is very fast, and the ping value is basically below 100ms, which is a machine from Jinan, Shandong Province.
but the response time for posting or replying posts is very slow, at least 10s. After clicking on the post, the lower left corner of the browser shows that it is waiting for a response from xxx.xxx.xxx (my website domain name), but in fact, the post has been successful. What"s wrong with this
instead of the server?

MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b32953-2be31.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b32953-2be31.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
Need Help?