Add dev-mode setting for forcing the use of C2

[geoand]

This setting allows users to opt-in to C2 when it makes sense (for example when running LLM inference via Jlama or Llama3.java)

[gsmet]

I think we might need to balance what the current default brings vs what it costs in some cases.

If it brings just a tiny bit more speed in standard cases and makes some use cases really really worse, it might make sense to just use C2 all the time.
Suggesting as you might miss this knobs entirely given it's quite advanced.

Now if the current default actually makes things a lot better in most cases then it makes sense to keep it.

[geoand]

C2 should not be used by default as it does come with a non-trivial startup penalty.
For example, in the rest-json quickstart on my machine the penalty was more than 300ms for the first start.

[gsmet]

OK, thanks for having a look. I was asking because from time to time, we are micro-optimizing because it doesn't cost us anything. It's worth revisiting when we actually identify a cost.

LGTM, then!

[geoand]

Yeah, I'm glad you brought it up as we haven't checked in a long time!

[quarkus-bot]

Status for workflow Quarkus CI

This is the status report for running Quarkus CI on commit 19e1a7b.

✅ The latest workflow run for the pull request has completed successfully.

It should be safe to merge provided you have a look at the other checks in the summary.

You can consult the Develocity build scans.

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Flaky tests - Develocity

⚙️ JVM Tests - JDK 17

📦 extensions/opentelemetry/deployment

✖ io.quarkus.opentelemetry.deployment.metrics.HttpServerMetricsTest.collectsHttpRouteFromEndAttributes - History

• Assertion condition defined as a Lambda expression in io.quarkus.opentelemetry.deployment.common.exporter.InMemoryMetricExporter expected: <true> but was: <false> within 5 seconds. - org.awaitility.core.ConditionTimeoutException

org.awaitility.core.ConditionTimeoutException: Assertion condition defined as a Lambda expression in io.quarkus.opentelemetry.deployment.common.exporter.InMemoryMetricExporter expected: <true> but was: <false> within 5 seconds.
	at org.awaitility.core.ConditionAwaiter.await(ConditionAwaiter.java:167)
	at org.awaitility.core.AssertionCondition.await(AssertionCondition.java:119)
	at org.awaitility.core.AssertionCondition.await(AssertionCondition.java:31)
	at org.awaitility.core.ConditionFactory.until(ConditionFactory.java:1006)
	at org.awaitility.core.ConditionFactory.untilAsserted(ConditionFactory.java:790)
	at io.quarkus.opentelemetry.deployment.common.exporter.InMemoryMetricExporter.assertCountPointsAtLeast(InMemoryMetricExporter.java:131)
	at io.quarkus.opentelemetry.deployment.common.exporter.InMemoryMetricExporter_ClientProxy.assertCountPointsAtLeast(Unknown Source)

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⚙️ JVM Tests - JDK 17 Windows

📦 extensions/opentelemetry/deployment

✖ io.quarkus.opentelemetry.deployment.metrics.HttpServerMetricsTest.collectsHttpRouteFromEndAttributes - History

• Assertion condition defined as a Lambda expression in io.quarkus.opentelemetry.deployment.common.exporter.InMemoryMetricExporter expected: <true> but was: <false> within 5 seconds. - org.awaitility.core.ConditionTimeoutException

org.awaitility.core.ConditionTimeoutException: Assertion condition defined as a Lambda expression in io.quarkus.opentelemetry.deployment.common.exporter.InMemoryMetricExporter expected: <true> but was: <false> within 5 seconds.
	at org.awaitility.core.ConditionAwaiter.await(ConditionAwaiter.java:167)
	at org.awaitility.core.AssertionCondition.await(AssertionCondition.java:119)
	at org.awaitility.core.AssertionCondition.await(AssertionCondition.java:31)
	at org.awaitility.core.ConditionFactory.until(ConditionFactory.java:1006)
	at org.awaitility.core.ConditionFactory.untilAsserted(ConditionFactory.java:790)
	at io.quarkus.opentelemetry.deployment.common.exporter.InMemoryMetricExporter.assertCountPointsAtLeast(InMemoryMetricExporter.java:131)
	at io.quarkus.opentelemetry.deployment.common.exporter.InMemoryMetricExporter_ClientProxy.assertCountPointsAtLeast(Unknown Source)

• Assertion condition defined as a Lambda expression in io.quarkus.opentelemetry.deployment.common.exporter.InMemoryMetricExporter expected: <true> but was: <false> within 5 seconds. - org.awaitility.core.ConditionTimeoutException

org.awaitility.core.ConditionTimeoutException: Assertion condition defined as a Lambda expression in io.quarkus.opentelemetry.deployment.common.exporter.InMemoryMetricExporter expected: <true> but was: <false> within 5 seconds.
	at org.awaitility.core.ConditionAwaiter.await(ConditionAwaiter.java:167)
	at org.awaitility.core.AssertionCondition.await(AssertionCondition.java:119)
	at org.awaitility.core.AssertionCondition.await(AssertionCondition.java:31)
	at org.awaitility.core.ConditionFactory.until(ConditionFactory.java:1006)
	at org.awaitility.core.ConditionFactory.untilAsserted(ConditionFactory.java:790)
	at io.quarkus.opentelemetry.deployment.common.exporter.InMemoryMetricExporter.assertCountPointsAtLeast(InMemoryMetricExporter.java:131)
	at io.quarkus.opentelemetry.deployment.common.exporter.InMemoryMetricExporter_ClientProxy.assertCountPointsAtLeast(Unknown Source)