Illegal mix of collations exception caused by Drupal 8 Autocomplete with Entity Reference View
Looking at a Recent log messages report of one of our Drupal 8 instaces, I came across this error message:
Set Limit for open files for MySQL on Ubuntu 16.04 with systemd
Sometimes you get the error
Out of resources when opening file './database/table.MYD' (Errcode: 24 - Too many open files)
To fix this on Ubuntu 16.04 you have to change the limits and to change the systemd-config: