JMETER: how to create a group of N threads where N is the number of lines in a file

Question

I have the following test plan:

I want to have 1 thread on each line of csv file.

How can I achieve it?

Can you elaborate? In plain Java you'd just `FIles.lines().parallel()` but you mention jmeter... — fge, Apr 06 '16 at 16:30
Are you asking how to create a group of N threads where N is the number of lines in a file? — Brandon, Apr 06 '16 at 16:35
I had this issue too, but gave up. Instead, I defined a parameter "totalThreads" on plan level with hard-coded value (based on spreadsheet size), and use it in the thread group definition as `${totalThreads}`. At least I can manage it in one place. — timbre timbre, Apr 06 '16 at 19:07
So you want JMeter to automatically pick the no. of rows in CSV and create no. of threads equal to no. of rows in csv? If that is your requirement then it is not possible with current jmeter capabilities. A workaround could be that first you run a threadgroup (having beanshell code that can read the number of rows. Store that into a variable). After that you can use it. There is not straight forward solution for it. — TestingWithArif, Apr 07 '16 at 05:04

score 1 · Answer 1 · edited Apr 07 '16 at 17:23

It is possible, but you will need to count lines in CSV file before jmeter starts, like:

In JMeter define "Number of threads" using __P() function like
```
${__P(threads,)}
```
You can pass threads property value via -J command-line argument like
```
jmeter -Jthreads=60 ....
```

You can use your operating system commands to count lines in CSV file like:

for MS Windows use "for" loop as Xoce 웃 Пepeúpa suggests, like create i.e. runtest.bat file like:

setlocal EnableDelayedExpansion
set "cmd=findstr /R /N "^^" PATH_TO_YOUR_FILE.CSV | find /C ":""

for /f %%a in ('!cmd!') do set threads=%%a

jmeter.bat -Jthreads=%threads% -n -t test.jmx ...

for Linux/Unix you can use wc and awk commands combination and run JMeter like:

./jmeter -Jthreads="$(wc -l PATH_TO_YOUR_FILE.CSV | awk {'print $1'})" -n -t test.jmx

Theoretically Linux way should be suitable for OS X as well.

See Apache JMeter Properties Customization Guide for more information on JMeter properties and ways of working with them

in logs I see: *jmeter.engine.StandardJMeterEngine: Starting ThreadGroup: 1 : Thread Group jmeter.engine.StandardJMeterEngine: Starting 0 threads for group Thread Group. jmeter.engine.StandardJMeterEngine: Thread will continue on error jmeter.threads.ThreadGroup: Starting thread group number 1 threads 0 ramp-up 0 perThread NaN delayedStart=false* — gstackoverflow, Apr 07 '16 at 15:29

JMETER: how to create a group of N threads where N is the number of lines in a file

1 Answers1