WooCommerce and 300.000 Products – How to optimize ?

Hello everybody !

I wanted to make a WordPress (3.5.1) & WooCommerce (2.0.3) website with more then 300.000 products but the project now hangs around with a few problems .

For now I’m running this project on a localhost (an i5 with 8 GB DDR3), with a lot of memory allocated to MySQL and Apache … but it still hangs.
I’m also using W3 Total Cache plugin for cache management. I’m also thinking if I buy a dedicated server with CloudFare cache servers this would run better …

Problems :

1. Even with W3 Total Cache,if a fresh new cache page needs to be created, displaying the parent categories (about 30 categs) takes a LOOOONG TIME .. maybe 2-3 hours .. and I don’t understand why .

2. For some reason, after adding more then 150.000 products to the database, WooCommerce stops showing the Subcategories as it is set on the option page … and it did work . I’m now forced to make a page with the following code :

[product_categories number="" parent="0"]

but this also works bad because it shows all categories and subcategories even if I used parent=”0″ and this code was taken from the woocommerce shortcodes webpage .

2.Does anyone have any idea on how to optimize WordPress & WooCommerce to work with such a big number of products !?

I would appreciate any good idea !