It should be Debug level.
https://github.com/alibaba/dubbo/blob/23084275bf695f41b5f84d927c351e9b2b04a2be/dubbo-monitor/dubbo-monitor-default/src/main/java/com/alibaba/dubbo/monitor/dubbo/DubboMonitor.java#L77
long[] numbers = reference.get();
            long success = numbers[0];
            long failure = numbers[1];
            long input = numbers[2];
            long output = numbers[3];
            long elapsed = numbers[4];
            long concurrent = numbers[5];
            long maxInput = numbers[6];
            long maxOutput = numbers[7];
            long maxElapsed = numbers[8];
            long maxConcurrent = numbers[9];
            String version = getUrl().getParameter(Constants.DEFAULT_PROTOCOL);
            
            URL url = statistics.getUrl()
                    .addParameters(MonitorService.TIMESTAMP, timestamp,
                            MonitorService.SUCCESS, String.valueOf(success),
                            MonitorService.FAILURE, String.valueOf(failure),
                            MonitorService.INPUT, String.valueOf(input),
                            MonitorService.OUTPUT, String.valueOf(output),
                            MonitorService.ELAPSED, String.valueOf(elapsed),
                            MonitorService.CONCURRENT, String.valueOf(concurrent),
                            MonitorService.MAX_INPUT, String.valueOf(maxInput),
                            MonitorService.MAX_OUTPUT, String.valueOf(maxOutput),
                            MonitorService.MAX_ELAPSED, String.valueOf(maxElapsed),
                            MonitorService.MAX_CONCURRENT, String.valueOf(maxConcurrent),
                            Constants.DEFAULT_PROTOCOL, version
                    );
            monitorService.collect(url);
            
            long[] current;