LongCounter does not accumulate

[canilsenlogiq]

I'm playing around with the opentelemetry-api dependency trying get metrics to work. I have made the Class below that runs some basic code every minute and .add(1) to my meter.

@Startup
@Stateless
public class MyScheduler {

    private static final LongCounter meter = GlobalOpenTelemetry.getMeter("schedule.meter")
            .counterBuilder("scheduled.task.counter")
            .setDescription("Counter testing in a schedule")
            .build();

    @Schedule(hour = "*", minute = "*/1", persistent = false, info = "MySchedule running every 1 minute")
    public void mySchedule() throws InterruptedException {
        Thread.sleep(2000);
        System.out.println("My Schedule running... with meter: " + meter.hashCode());
        meter.add(1, Attributes.of(AttributeKey.stringKey("schedule.name"), "mySchedule"));
    }

}

However, when I look into my index (using elastic observabiliy) I find that all my counter values are 1, they do not seem to add/accumulate over time.

Example result:

{"@timestamp": "Oct 17, 2025 @ 13:50:00.262", "scheduled.task.counter": 1, "service.framework.name": "schdule.meter", "labels.schedule_name": "mySchedule" }
{"@timestamp": "Oct 17, 2025 @ 13:51:00.262", "scheduled.task.counter": 1, "service.framework.name": "schdule.meter", "labels.schedule_name": "mySchedule" }
{"@timestamp": "Oct 17, 2025 @ 13:52:00.262", "scheduled.task.counter": 1, "service.framework.name": "schdule.meter", "labels.schedule_name": "mySchedule" }
{"@timestamp": "Oct 17, 2025 @ 13:53:00.262", "scheduled.task.counter": 1, "service.framework.name": "schdule.meter", "labels.schedule_name": "mySchedule" }
{"@timestamp": "Oct 17, 2025 @ 13:54:00.262", "scheduled.task.counter": 1, "service.framework.name": "schdule.meter", "labels.schedule_name": "mySchedule" }

I was expecting that for every execution the scheduled.task.counter would accumulate/increase.

I'm very new to OpenTelemetry and the opentelemetry-api dependency, so I might miss-use the whole thing. Could someone please clarify what I'm misunderstanding or doing wrong here?

Stuff I have tried
I have made sure both the Meter and LongCounter instance is reused.
I have tried with both Context.root() and Context.current().
I have tried not reusing the Meter and LongCounter instance.
I have tried with and without adding Attributes when using the .add() method.

[trask]

hi @canilsenlogiq, my first guess is that you're seeing DELTA metrics instead of CUMULATIVE metrics. you could try updating multiple times per minute to confirm this (default export is once per minute)

[canilsenlogiq]

hi @canilsenlogiq, my first guess is that you're seeing DELTA metrics instead of CUMULATIVE metrics. you could try updating multiple times per minute to confirm this (default export is once per minute)

I increased the the frequency of the job, and I'm now getting "scheduled.task.counter": 4 as is it running four times every minute.

Maybe I have thought about it wrong, but I thought this counter would not reset between the jobs. Does this mean it is set to DELTA instead of CUMULATIVE? I thought about trying CUMULATIVE earlier, but saw that CUMULATIVE was default on the agent, so never tried. I'm using the elastic-otel-javaagent, which is supposed to be a small wrapper on-top of the opentelemetry-javaagent, maybe the elastic agent have DELTA as default.

But the more I'm thinking about it, the more confused I'm getting. If I'm able to get this counter to increase, I assume it would reset on server or application restart. Guess I will have to play around some more.

[trask]

maybe the elastic agent have DELTA as default

cc @jackshirazi @JonasKunz @SylvainJuge

[jackshirazi]

yes, the Elastic Distribution of OpenTelemetry Java agent has delta as default