Deepstream docker images is too large

Please provide complete information as applicable to your setup.

• Hardware Platform (Jetson / GPU) t4
• DeepStream Version 5.1
• JetPack Version (valid for Jetson only)
• TensorRT Version 7.2
• NVIDIA GPU Driver Version (valid for GPU only) 440
• Issue Type( questions, new requirements, bugs) questions
• How to reproduce the issue ? (This is for bugs. Including which sample app is using, the configuration files content, the command line used and other details for reproducing)
docker build -t my-deepstream .
• Requirement details( This is for new requirement. Including the module name-for which plugin or for which sample application, the function description)
I didn’t add any thing to my dockerfile, why the new image is 3G larger than the old one.

FROM 5.1-21.02-samples 4edbe80901c3 6 months ago 6.87GB