Hi guys,
After some investigation I found information about a bug which is fixed in the upcoming release of WordPress (4.3.1). I just tried it myself and everything works like a charm now!!
Check out this article and change the line in the taxonomy.php file (don’t forget to backup the file). Than create the plugin file, save it and visit your website. Within a minute I could access the media library again.
There is some text about a 4 minute extreme load when activating the plugin, but that has been fixed, so don’t worry.
https://wordpress.org/support/topic/high-cpu-load-after-update-to-v43?replies=17#post-7330770
I am also seeing a lot of memory exhausted errors in the errorlog, sometimes with relations to wp-compression.
I am even not seeing images in the media library 🙁
Do you mean when you want to add an image, the media library keeps loading (turning circle) and no images are shown?
I have that situation since the upgrade to 4.3
