Обсуждение: what case does xid wraparound warning messages like example emit?

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what case does xid wraparound warning messages like example emit?

От
Takuma Hoshiai
Дата:
Hi all, 

I have a question about xid wraparound.  
The document below say that warning occurs when transactionId which I can use 
is reduced to less than 11,000,000. 

https://www.postgresql.org/docs/11/routine-vacuuming.html#VACUUM-FOR-WRAPAROUND
==============================
If for some reason autovacuum fails to clear old XIDs from a table, the system will begin to emit warning messages like
thiswhen the database's oldest XIDs reach ten million transactions from the wraparound point:
 

WARNING:  database "mydb" must be vacuumed within 177009986 transactions
HINT:  To avoid a database shutdown, execute a database-wide VACUUM in "mydb".
==============================

But example message of document wrote "within 177009986 transactions".  
What case do I can show transaction over 11,000,000 ?


Best regards,

-- 
Takuma Hoshiai <hoshiai@sraoss.co.jp>