Overview

Gunicorn 20.1, released on February 12, 2021, is a maintenance release fixing security and stability issues.

Main Features

Security fixes

Fixes vulnerabilities in HTTP header parsing and improves validation of incoming requests.

python 
# gunicorn.conf.py
bind = '0.0.0.0:8000'
workers = 4
worker_class = 'sync'
limit_request_line = 4094
limit_request_fields = 100
limit_request_field_size = 8190

Worker stability

Improved worker restart handling and signal management for better reliability in production.

python 
# gunicorn.conf.py - production configuration
workers = 4
timeout = 30
graceful_timeout = 30
max_requests = 1000
max_requests_jitter = 50
preload_app = True

Sources