PT-ONLINE-SCHEMA-CHANGE - possible time of running

Hello guys,

I would like to use PT-ONLINE-SCHEMA-CHANGE for reclaiming free space of our production DB. The things is that the DB takes 2.3TB of space, so the question is, do you maybe know how much time the PT-ONLINE-SCHEMA-CHANGE will run in order to ALTER so huge DB?

Thank you in advance,


Hi there le_den, thanks for your question.

The dev team suggested that you could try the --dry-run option to see how long it takes to at least nibble at the table in question, from there you might be able to draw a best case estimate… Here’s a link:

See how you get on?

Hi Lorraine,

And thank you for prompt response. I’ll try that.