I have process which executes query like below on Mysql(InnoDB) slave
INSERT ignore INTO user_profile_temp (some_fields)
select some_fields from user_profile
user_profile is bigtable of 8GB which will take 1 to 2 hour with HDD.
Because of this query , replication(master to slave) is waiting in queue to get above query getting complete. There can be lag of 1 to 2 hours.
Lag is happening because of select query.As select query will acquire shared lock only at row level which mean replication records not impacting current read in process , should be able to update the record parallely.
My question is does replication process waits if any user process running at that instant or it can run in parallel if it is not impacting same rows/tables?