Need Clarification

[sumeetb]

Hi,

I faced lot of issues with Jmeter and other performance tool and this tool seems to be really nice. I have just started learning locust tool for performance testing. I have some basic questions regarding the same.

1.Single Locust class resembles single user as per the document, is it mean if we want to simulate thousands of user’s then we need to define thousand locust classes? –c command line option represents number of clients (users) but I think it would create multiple instance of same class which would represent cloning of users. Please clarify.
2.How the test data can be controlled? Does it provide mechanism to input test data for example users information’s (username and password), different files to be uploaded by different users etc from external file like csv/excel/xml? I didn’t find anything in documents

Could you please clarify above queries?

Thanks,
Sumeet

[Jahaja]

Hi Sumeet,

1. No, the idea is that you write a Locust class that simulates some kind of user. Most often you only need one Locust class that simulates the normal user. What sets them apart is the randomness of the tasks picked for each instance/user and the state that you can save for each user - and use in subsequent requests. Normally you write code yourself to assign each user/instance a unique id or username so it can perceed to login or something similar.
2. I've partially already answer that in 1, but to clarify you need to write your own code to set data each user/instance. Perhaps just randomizing from a list or between some number range is sufficient for your use-case. This list could of course be read from a csv or similar using the normal python libraries.

[sumeetb]

Hi Jahaja,

Thanks a lot for clarifying my doubts. I did use external CSV as test data and passed on to different user/instance. It is working fine now. I have couple of more questions and hope you don’t mind to clarify the same. :)

1.Host parameter needs to be set either from command line or in main locust class. But in my scenarios we have multiple hosts to be used to send and receive data. Like POST on host1, GET on host2 etc. Is there any way I can have multiple host parameters to be used in the “taskset” for the different requests in locust class? The hard coded URL can be used while sending/receiving requests in task-set class but then it will create connection at the time of sending/receiving request which I think won’t be right way to do it.

2.Any user can pick any task as per the weighted for the task decorator even after completing their assigned task? Or at the start of test if particular user has been assigned specific random task then it is going to run the same task again and again throughout the test?

Thanks,
Sumeet

[heyman]

Hi sumeet!

1. By default Locust's client runs with keep_alive turned off. So normally, a connection will be made for each request anyway. There are plans for making the client more "pluggable" so that you can easily roll your own client, but until that is implemented, you could override the init method of the Locust class (

   locust/locust/core.py

   Line 93 in 2e725c4

   def __init__(self):

   ) to initialize the client with the base host of your choice.
2. Once a Locust user has executed a task in a taskset, it will pick another task randomly as per the tasks' weight, to execute (after it has been idling during it's wait time).

[heyman]

I'm closing this now, but feel free to re-open it if you have more questions.

[ruchikaChawla]

Hello Everyone,

I were using jmeter till now but i saw it is taking lots of resources and memory to run,
so now i started reading locust. i am new to locust.
i want to use locust in no-web mode e.g $ locust -f locust_files/my_locust_file.py --no-web -c 1000 -r 100 but same as above question , i dont want to hard code the URL or you can say header parameter like unique request id and all, i want to pass it from command line, like we can pass in jmeter and we can get it in configuration file using __P() function.
how we can get the same thing in locust, i know the way of using environment variables but i do not want to use this.