While smush.it is working (compressing an image), the website hangs for all users until the 'smushing' is complete. This is usually several seconds, and isn't great.
When I select 20 images in the media library and 'bulk smush' them, the whole website hangs for all users for up to a minute. Which is unacceptable.
The site I'm working on now has ~30k images, which according to my estimates might take ~20 hours to smush if I did them all in bulk. That's 20 hours of downtime for the site, which is obviously not even worth considering.
FYI the site is running WooCommerce, the images are product images (6 sizes in total for each image) and it's all running on a powerful dedicated server with 16GB RAM.
Why is smush.it eating up all the resources? Why can't it run in the background using a smaller amount of resources, even if it this means it smushes more slowly, but allows the website to function as normal?