[slow query]Every morning at 3 o'clock, there are many slow queries.

[coffee]

OS：CentOS7.9
Mysql：5.7.36
Zabbix-server：5.0.14

Every morning at 3 o'clock, there are many slow queries. I have setting the HousekeepingFrequency=0 and switched the database to save to SSD,help me.

26649:20240125:030209.977 slow query: 117.962144 sec, "update item_discovery set lastcheck=1706122812 where itemid in (483272,483273,483274,483275,483276,483277,483278, 483279,483280,483281,483282,483283);
26643:20240125:030209.977 slow query: 115.317600 sec, "update item_discovery set lastcheck=1706122814 where itemid in (58719,58720,58722,58723,58725,58726,58728,58729,5 8731,58732,58734,58735);
26621:20240125:030209.979 slow query: 117.968000 sec, "update item_discovery set lastcheck=1706122812 where itemid in (139182,139183,139184,139185,139186,139187,139188, 139189,139190,139191,139192,139193,139194,139195,1 39196,139197,139198,139199);
26628:20240125:030209.981 slow query: 119.190419 sec, "update item_discovery set lastcheck=1706122810 where itemid in (484385,484386,484387,484388,484389,484390,484391, 484392,484393,484394,484395,484396,484397,484398,4 84399,484400,484401,484402);
27228:20240125:030209.982 slow query: 82.767325 sec, "update hosts set disable_until=1706122907 where hostid=10461"
...



For more slow queries, please refer to the attachment

[cyber]

What goes on in your surrounding environment? I would suspect backups being done at that time or something, slowing down your env...

[coffee]

You're right, I found a backup task while checking the scheduled tasks. I'll stop and observe again. Thank you