libvips和ImageMagick都是图像处理库。Rails文档上说libvips比ImageMagick快10倍，内存占用只有ImageMagick的1/10。

安装libvips和libjpeg-turbo-dev

sudo apt install libvips-dev libjpeg-turbo8-dev

去掉Gemfile中image_processing的注释

gem "image_processing", ">= 1.2"

安装ruby-vips

gem "ruby-vips", "~> 2.2"

配置Active Storage使用vips

# config/initializers/active_storage.rb
Rails.application.config.active_storage.variant_processor = :vips