If using Astra is causing your computer's performance to slow down, you can cut the CPU in half by switching to ECO mode directly in the plugin.
Open Astra in your DAW, and head to the upper right hand corner and go to "Quality"
You will have the option to toggle between "FULL" and "ECO"
Select "ECO" in order to reduce the CPU in half. There will be no noticeable sound changes for most presets.