Frequently Asked Questions

On this page, we gather frequently asked questions.

If you don't find the answer to your question, please explore the documentation for a few minutes. You still don't get your answer? Don't hesitate to create a question issue or leave a message on the chat.

General

Why use QuickPerf?

Explanations here.

QuickPerf annotations seem not executed

Check that the test is a QuickPerf test.

Global annotations seem not executed

Check that the class implementing SpecifiableGlobalAnnotations uses the org.quickperf package.

💡 What is a global annotation?

JVM

Is a long time spent doing GC?

The fastest way to answer this question with QuickPerf is to use ProfileJvm annotation. This annotation displays the GC time on the console:

GARBAGE COLLECTION           
Total pause     : 1,264 s   

This information can help choose a heap size, for example, with HeapSize annotation, to limit GC duration and test length.

org.openjdk.jmc:flightrecorder.rules.jdk:pom:7.0.0 not found

👉 Maven

The error message contains Failure to find org.openjdk.jmc:flightrecorder.rules.jdk:pom:7.0.0 in.

Add the https://adoptopenjdk.jfrog.io/adoptopenjdk/jmc-libs repository to the POM file:

<repositories>
        <repository>
            <id>AdoptOpenJDK</id>
            <name>AdoptOpenJDK</name>
            <url>https://adoptopenjdk.jfrog.io/adoptopenjdk/jmc-libs</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
</repositories>

👉 Gradle

Add the https://adoptopenjdk.jfrog.io/adoptopenjdk/jmc-libs repository to the build.gradle file:

repositories {
	mavenCentral()
	maven { url 'https://adoptopenjdk.jfrog.io/adoptopenjdk/jmc-libs' }
} 

SQL

How to detect N+1 selects

Explanations here