Jmeter.properties suggest the default value is 1 second for backend_graphite.send_interval:

########################
# Graphite Backend
########################
# Send interval in second
# Defaults to 1 second
#backend_graphite.send_interval=1


Also a comment in GraphiteBackendListenerClient.java suggests it needs to be 1 second:

    public void setupTest(BackendListenerContext context) throws Exception {
        ...


        // Don't change this as metrics are per second
        this.timerHandle = scheduler.scheduleAtFixedRate(this, SEND_INTERVAL, SEND_INTERVAL, TimeUnit.SECONDS);
    }

but the default for SEND_INTERVAL is 5 seconds in the code:

    private static final long SEND_INTERVAL = JMeterUtils.getPropDefault("backend_graphite.send_interval", 5);

The good bit is that it's easy to fix temporarily (until it is fixed in the code) by actually uncommenting/setting backend_graphite.send_interval=1.

Why is this a problem? When creating graphs to display request per second metric (using either the a.count, h.count, ok.count, or ko.count) the numbers are inflated to those of 5 second window when using defaults.

This bugs seems to be introduced with the addition of timeboxed sliding window feature.

We noticed the change when we upgraded JMeter from 3.1 to 3.3. Without changing any of the relevant settings our graphs showing x.count stats jumped to x5 of their previous values.