Env

• GCC 11.3
• CMake 3.22.1
• VSCode 1.78.2 with MS C++ Extension Pack
• Node 18.15.0 (Optional - for test client)
• Ubuntu 22.04 LTS
• MSI Modern 15 (i5 1155G7 - 16GB RAM)

Prerequisites

Default maximum number of descriptor files can be opened in Ubuntu OS is 1024, we must increase this number in order to handle 5k. To increase the limitation, run ulimit -n 10000

How to compile?

Option 1: VSCode and CMake extension

• Select CMake: Build from VSCode command

Option 2: Command line

• mkdir build
• cd build
• cmake ..
• make

How to test?

With simple spec test file (tcp-server_spec.cpp)

• Compile the project
• Execute test ./build/simple-tcp-server-tests --gtest_filter=TCPServerTest.SimpleServer
• Observe the 5k connections are made

Unknown issue happens when I run both tests of TCPServerTest at once that causes the test client waits forever. It is not worth taking time to solve it as they can be executed separately. For now, I decide to keep it as is.

Benchmarked with simple node client

• Install npm test client by cd test-client && npm install
• Start tcp server ./build/simple-tcp-server
• Start test client cd test-client && npm test
• Observe the output

Benchmarked with tcpgoon

• Start tcp server ./build/simple-tcp-server
• Execute tcpgoon benchmark session by tcpgoon run localhost 8080 --connections 5000 --sleep 1 -y
• Observe the output

Test simple chat server with Netcat

• Start chat server ./build/simple-chat-server
• Start a few Netcat sessions by nc 127.0.0.1 8080
• Type a message in one Netcat session window
• Observe the broadcasted messages in other Netcat window