Guessing this may take an Xpert's reply, but I'm wondering if anyone can explain how the Database Migrator performs the delete of tables (scrub). It seems it is doing it in a way that the delete must be logged. I'm wondering if this could instead use the TRUNCATE function to NOT have it all logged.
I ran an migration with just SYSTEM on a clean 5.x install.
The overall migration took about 3 minutes, and the scrub took less than 2 seconds.
INFO - Scrub tables from target took: 1.146 s
But then I immediately ran it again, and the migration took close to 4 minutes, and the scrub took 30 seconds.
INFO - Scrub tables from target took: 31.52 s
This became more of an issue after I ran a migration as ALL and then wanted to run another migration.
At this point, I took a SQL backup of the 5.x DB right after a clean install, so it's very small. I'm going to save that backup and restore it prior to running my test migrations. But it appears if you want to migrate several times, it takes a while and can eat up log space because it's performing the scrub in a fashion that is logged. Perhaps the procedure could just recommend taking a SQL backup prior to running migration after shutting down the system? I'd think that'd be when you'd want a cold backup anyways. And then use TRUNCATE to clear everything?