Concurrent Users
Salmon v0.2.3 can handle up to at least 100 simultaneous users interacting with the system and answering questions. Here’s the setup:
Launched Salmon on a Amazon EC2
t3.large
instance.Simulated client response time using the most similar task I could find 2. Response times were a modified Gaussian random variable with mean 750ms and standard deviation 250ms (modified so always greater than 200ms).
Each client for 50 responses.
Here are the performance results with that setup:
![../_images/delay-histogram.png](../_images/delay-histogram.png)
This performance is pretty good! Most of the responses return in around 400ms. How do the extremes perform?
![../_images/delay-percentils.png](../_images/delay-percentils.png)
45 of a users queries will return in less than 500ms if the user answers 50 questions and there are 102 simultaneous clients.
- 2
Specifically, a spatial configuration task with 3 elements. I pulled number from Figure 6 of Palmer et. al [palmer].
- palmer
“What are the shapes of response time distributions in visual search?” Palmer, Horowitz, Torralba, & Wolfe (2011). Journal of experimental psychology. https://doi.org/10.1037/a0020747