Question about validation-timeout behavior in HikariCP

[songpang]

Hello,

I conducted a test to verify how the validation-timeout setting works in HikariCP under specific conditions.

Here is my setup:

A Spring Boot application running locally
A MySQL database running locally
A toxiproxy-server running locally, forwarding port 3306 to 3307, and adding a 6000ms latency

I wanted to observe how validation-timeout behaves in this situation. While making normal API calls, I added latency in the middle of the test. As expected, a log message indicating validation failure appeared.

However, based on the code:

final var validationSeconds = (int) Math.max(1000L, validationTimeout) / 1000;

If validation-timeout is set to 2500, the failure log should appear after 2 seconds, but instead, it appears 4 seconds after the API call.

When I set it to 1500, the log appears 2 seconds later.
When I set it to 3500, the log appears 6 seconds later.
From this pattern, it seems that the actual validation-timeout value becomes twice the expected value after dividing by 1000. What could be causing this issue?

Additional Test

I also performed another test where I disabled Wi-Fi after starting the local application to see how it behaves. In this case, it worked as expected.

With validation-timeout set to 2500, the log appeared after approximately 2 seconds.
Could you help me understand why this discrepancy occurs?

Thank you.