bug: limit-req cannot limit access

[dimon-v]

Current Behavior

When using OpenResty Limit Req, Set the rate to 200 Burst setting 1, after using WRK stress testing, I calculated that the number of 200 status entries in the access log is less than the rate （ see bingoohuang/blog#209

lua_shared_dict my_limit_req_store 100m;

server {
listen 8700;
default_type text/html;

location / {
    return 200 OK;
}

location /limit {
    access_by_lua_block {
        local limit_req = require "resty.limit.req"

    -- 限制每秒 100 个请求 (rate)，以及 1 的等待队列 （burst), 超过每次 300，直接拒绝
    local rate = tonumber(ngx.var.arg_rate or 100)
    local burst = tonumber(ngx.var.arg_burst or 1)
    local lim, err = limit_req.new("my_limit_req_store", rate, burst)
    if not lim then
        ngx.log(ngx.ERR, "failed to instantiate a resty.limit.req object: ", err)
        return ngx.exit(500)
    end

    -- 以远端IP为限制 key
    local delay, excess = lim:incoming(ngx.var.binary_remote_addr, true)
    if excess == "rejected" then
        ngx.status = 503
        return ngx.exit(503)
    end

    ngx.say("OK delay: ", delay, ", rate: ", rate, ", burst: ", burst, ", excess: ", excess)
    return ngx.exit(200)
}

Expected Behavior

According to the limit req document, requests with a request rate exceeding (rate+burst) will be directly rejected, such as setting rate=100, Burst=1 expects requests with QPS greater than 101 per second to return 503

Error Logs

No response

Steps to Reproduce

1、run apisix and set route with limit-req
2、use wrk testing
3、grep access log count

Environment

• APISIX version (run apisix version): 3.8.1
• Operating system (run uname -a): 3.10.0-1160.31.1.el7.x86_64 change: added doc of how to load plugin. #1 SMP Thu Jun 10 13:32:12 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
• OpenResty / Nginx version (run openresty -V or nginx -V): nginx version: openresty/1.21.4.2
  built by gcc 9.3.1 20200408 (Red Hat 9.3.1-2) (GCC)
  built with OpenSSL 3.2.0 23 Nov 2023
• etcd version, if relevant (run curl http://127.0.0.1:9090/v1/server_info): {"id":"66356a45-bcc5-4a5a-9318-210342728ebd","hostname":"nginx-gray02","version":"3.8.1","boot_time":1716876699,"etcd_version":"unknown"}
• APISIX Dashboard version, if relevant:
• Plugin runner version, for issues related to plugin runners:
• LuaRocks version, for installation issues (run luarocks --version):

[kayx23]

Is this issue the same as #11288? If so, could you keep one open with the summarized info? Thanks.