In this link I see the nginx says:

Zone – Defines the shared memory zone used to store the state of each IP address and how often it has accessed a request‑limited URL. Keeping the information in shared memory means it can be shared among the NGINX worker processes. The definition has two parts: the zone name identified by the zone= keyword, and the size following the colon. State information for about 16,000 IP addresses takes 1 ;megabyte, so our zone can store about 160,000 addresses.

My questions and what I don’t understand are the following:

1. How long it takes for nginx to clear the memory of stored IP addresses?

In this part, it says:

limit_req_zone $binary_remote_addr zone=mylimit:10m rate=10r/s;

The 10m by the previous definition, it means 1,600,000 IP addresses.

2. For how long the nginx stores these IP addresses and how it clears them?

The purpose of this question is this:

I set a rate limit like this:

limit_req_zone $binary_remote_addr zone=mylimit:1m rate=2r/s;

I create a very simple html page which has one request only. So technically I can refresh this page 2 times per second and for the 3rd time to refresh, I should be faced with an error like 503 or 429.

Up to this point, everything is fine. But after a couple of seconds 15 seconds waiting and doing nothing, I refresh the page but I still get 503 or 429 error.

I even did systemctl reload nginx but I still see error page. Then I did systemctl restart nginx but nothing changed.

Am I doing anything wrong here? Did I misunderstood anything here? Or there are some topics or subjects I don’t know?