Description:
Currently there is no way to determine when a transaction started in "user time" (as opposed to the TIMER_START value that can't be converted to a human readable time).
This will be particularly useful in the events_transactions_current table for ongoing transactions as it will allow the user to calculate the age of the transaction.
Note: Currently you can get that information for InnoDB by joining through the performance_schema.threads table to the information_schema.INNODB_TRX table, but that is not lock free (INNODB_TRX requires similar locks as SHOW ENGINE INNODB STATUS) and is not storage engine independent.
Long running transactions is a common cause of issues with bloated InnoDB history lists, lock contention, etc. The Performance Schema transaction tables is the natural place to look for information about such transactions.
How to repeat:
N/A
Suggested fix:
N/A