Nginx studies

A set of studies about how Nginx works and how it interacts with the operating system under the hoods.

Each directory is a study, with a README file containing the instructions to reproduce it, some logs and notes.

• sendfile
• tcp_nopush
• TODO: kTLS
• TODO: http/2
• TODO: http/3

Requirements

All studies requires an OpenResty docker image with debug flag and strace.

1. Clone the docker-openresty repo

2. Add the flag --with-debug inside the RESTY_CONFIG_OPTIONS in file alpine/Dockerfile:

   ARG RESTY_CONFIG_OPTIONS="\
   --with-debug \
   --with-compat \
   // other lines

3. Add the instruction RUN apk add strace before the copy of Nginx conf files in alpine/Dockerfile:

   # Add additional binaries into PATH for convenience
   ENV PATH=$PATH:/usr/local/openresty/luajit/bin:/usr/local/openresty/nginx/sbin:/usr/local/openresty/bin
   
   RUN apk add strace
   
   # Copy nginx configuration files
   COPY nginx.conf /usr/local/openresty/nginx/conf/nginx.conf

4. Build the Nginx:

   docker build -t openresty-with-debug:latest -f alpine/Dockerfile .

How to run the images of the studies

1. Run Nginx:

   make run

2. In another terminal, attach the strace process to Nginx:

   make strace

3. In another terminal, reload the Nginx:

   make reload

4. Make the requests. Each study has its own instructions about this step.