Purge all option with a lot of posts

[lfbn]

If the website has a lot of posts, for me 12k, the "purge all" option wouldn't work. It gets out of memory.

Using WP to get posts, WP queries to get taxonomies and this is very huge. Tested with a raw query, and for a website with 12k posts also doesn't work.

Can this be done if we save like an index with the keys we saved in Redis? Or maybe have a script that will delete them all.