We have been trying for a while now to upgrade magento from 1.4.1 to 1.6.2
While attempting to upgrade from 1.4.1 to 1.5.1 and then 1.5.1 to 1.6.2 I let the installer run for over 12 hours and the cpu on our server was maxed out with mysql services. I have read that this can be due to a large amount of orders, we have 18000 orders in our system, I cant see this being too much for magento but it seems that it is.
Is there anyway around having to delete all of the orders to be able to upgrade?
Update: I was able to upgrade to 1.5.1 by removing all orders, I am currently running the upgrade to 1.6.2 and the cpu is maxing out, we will see if this works to 1.6.2 Even if it does I would like to figure out how to transfer our orders over to the new version too.