nGrinder Study

[iamabear09]

nGrinder Component

Controller

• a web application that enables the performance tester to create a test script and configure a test run

Agent

• a virtual user generator that creates loads.

Install

Docker Image https://hub.docker.com/r/ngrinder/controller

Controller

docker run -d 
-v ~/ngrinder-controller:/opt/ngrinder-controller \
--name controller \
-p 80:80 -p 16001:16001 \
-p 12000-12009:12000-12009 \
ngrinder/controller

a data folder

• /opt/ngrinder-controller
• to maintain test history and configuration data.

In order to keep the data persistently,

• map the folder /opt/ngrinder-controller on the container to a folder on your host .
• `-v ~/ngrinder-controller:/opt/ngrinder-controller

ports

• 80: Default controller web UI port.
• 9010-9019: agents connect to the controller cluster thorugh these ports.
• 12000-12029: controllers allocate stress tests through these ports.

Agent

we strongly recommend

• to run nGrinder agent containers on the physically different machines from the one where controller is installed.

other reason

• dockers running on the same machine cannot communicate each other without having to use an additional docker networking solution.

나는 컴퓨터가 한 대 인데, 어떻게 다른 장치에서 agent container를 실행하라는 얘기지...?

[iamabear09]

Virtual-User

Virtual Users

• threads
• Instead of mimicking the user real behavior, we focus on how to make the server reach its limit.

vuser limit

• as 2000 with 4GB ram and 2 core CPU agent machines.
• 8000 vusers can be run if you have 8GB and 4 core CPU machines.

Process-and-Thread

processes and threads

• to simulate multiple users.
• configure process-thread count calculation logic
  • by configuring process_and_thread_policy.js.

Processes size

• more than 10 easily cause thrashing by memory swapping in the agent
  • if your agent has less than 4GB memory
• If there are many number of processes,
  • they would exceed the agent machine’s physical memory size.
• Please set it less than 10

Thread size

• If you increase the thread number more than 200,
  • it might cause problems either
• If you have no idea on this, Just let the nGrinder calculate automatically.

Max Vuser setting we have some experiment how many vusers a agent can handle

• 4000 vusers can be supported
  • by a single 4GB memory agent
  • if each test doesn't use takes much memories.
• If you like to increase the max vuser limitation,
  • please configure agent.max.vuser in system.conf.

thread-ramp-up

차근차근 부하를 올려가면서 테스트를 진행한다. 따라서 어느 시점부터 나의 Server가 견디지 못하는지 파악할 수 있다. 만약 Vuser가 계속 증가했는데, TPS는 증가하지 못하는 지점이 나오면 그 지점이 Server 견디지 못하는 지점이다.

[iamabear09]

Groovy-Script

• you can reuse the existing development experiences with JUnit and IntelliJ.
  • When you decide to write scripts with groovy in maven structure,
• 2 times more virtual user count(especially thread count) per agent.

Groovy Script가 좋으니 이거 써라... 이런 말이다.

Groovy-Script-Structure

Groovy Script Structure

• is based on JUnit

Create Goorvy Maven Project

• If you created Goorvy Maven Project in script creation dialog box in nGrinder,
  • you can enjoy the this excellent approach in your current IDE.

    IDE 기능을 사용하여 Script를 작성할 수 있다.