Resolution: Not a bug
Affects Version/s: 4.2.3
Fix Version/s: None
Report from the forums:
Monitoring plugin have a very strange code, that inserts messages into database.
It select count of all messages from database with query: SELECT COUNT FROM ofMessageArchive
Next, this number increased by 1, and inserted into database as “messageID” field.
This code generates heavy load on database with huge number of archived messages and online users.
For example - for me, query executes 3-4 seconds (SSD, MSSQL, 75 millions messages stored).
Database can have autoincrement field, that works much faster.
Though I don't know how easy it would be to retrofit an auto-increment field to all supported databases. It may be more practical to use a JiveID, for example.