One large machine or cluster of small machines for Jmeter load generator in load testing?
According to KISS principle it is better to go for a single machine assuming it is capable of conducting the required load.
- Make sure you're following JMeter Best Practices
- Make sure you have monitoring of baseline OS health metrics (CPU, RAM, swap, network and disk IO, JVM statistics, etc.)
- Start with low number of users and gradually increase the load until you reach the desired throughput or limit of any of the monitored metrics, whatever comes the first. If there will be a lack of CPU or RAM or something - see what could be done to overcome the limitation.
More information: What’s the Max Number of Users You Can Test on JMeter?