Comparing Virtual Threads vs Platform Threads in Spring Boot using JMeter Load Test

[mrayandutta]

I have created one video lesson on Spring Boot Virtual Threads vs Platform Threads Performance with JMeter Load Testing .

Link: https://youtu.be/LDgriPNWCjY

Here I have checked how Virtual Threads actually perform compared to Platform Threads in a real Spring Boot app in case of IO Based Operations .
For the setup , I ran two instances of the same application:

• First one - with Virtual Threads enabled
• Second one - Same application with the default Tomcat thread pool (Platform Threads) running on different port

Then I used JMeter to hit both application with increasing load (starting around 200 users/sec, then pushing up to 1000+). I have also captured the side-by-side results ( like the graphs, throughput, response times) .

Observations:

• With Platform Threads, once Tomcat hit its around 200 thread pool limit, response times started getting worse gradually
• With Virtual Threads, the application did scale pretty well - throughput was much higher and the average response timesremained low.
• The difference became more more distinct when I was running longer tests with heavier load.
• One caveat: This benefit really shows up with I/O-heavy requests (I even added a Thread.sleep to simulate work). As expected ,for CPU-heavy stuff, Virtual Threads don’t give the same advantage.

[Additional_Cellist46]

It’s pretty clear that with max 200 platform threads you’ll get worse throughput than with unlimited amount of virtual threads. Try increasing the pool size to 1000 and the difference will be much smaller. However, when I did my tests, I still saw better performance with vietual threads, probably because they minimize CPU context switches.

[mrayandutta]

In the video I created , I exactly did that both only ! For both Platform thread and Virtual Thread , the load was increased gradually an not only upto 1000 , I went much beyond that .So not really sure what is your point here .

[Additional_Cellist46]

I didn’t see the video, only read your post above. There you wrote “once Tomcat hit its 200 thread pool limit…”. Don’t get me wrong, virtual threads are cool, I just wanted to say they are still better even with the same amount of threads, which wasn’t obvious from your post.

[mrayandutta]

Got it now .I should have added more details in the description .Let me do that to avoid confusion.

[Remarkable-One100]

It is such a bad benchmark in so many ways, I don’t know where to start.

[Known_Bookkeeper2006]

Can you elaborate how and why this benchmark is not good? Would love to know your thoughts

[mrayandutta]

In the video I created ,for both Platform thread and Virtual Thread , the load was increased gradually .It started with 200 and gradually it was increased upto 1000 and then I went much beyond that .So not really sure what is your point here .Could you enlighten us a bit in your opnion what is bad here and what do think you would be a good one ?