Debug freezing test on CI.

dd-java-agent/instrumentation/lettuce-4/build.gradle

@@ -1,4 +1,3 @@
-
 muzzle {
   pass {
     group = "biz.paluch.redis"

gradle/configure_tests.gradle

@@ -1,5 +1,7 @@
 import java.time.Duration
 import java.time.temporal.ChronoUnit
+import java.util.concurrent.Executors
+import java.util.concurrent.TimeUnit
 
 def isTestingInstrumentation(Project project) {
   return [
@@ -125,7 +127,7 @@ if (!project.property("activePartition")) {
   }
 }
 
-tasks.withType(Test) {
+tasks.withType(Test).configureEach {
   // https://docs.gradle.com/develocity/flaky-test-detection/
   // https://docs.gradle.com/develocity/gradle-plugin/current/#test_retry
   develocity.testRetry {
@@ -134,3 +136,65 @@ tasks.withType(Test) {
     }
   }
 }
+
+tasks.withType(Test).configureEach {
+  doFirst {
+    // This manipulation is requred to move files into folder
+    // that will be collected by `collect_reports.sh` script.
+    String buildDir = layout.buildDirectory.asFile.get().absolutePath.replace("dd-trace-java/dd-java-agent",
+      "dd-trace-java/workspace/dd-java-agent")
+
+    def dupmsDir = new File(buildDir, "dumps")
+    dupmsDir.mkdirs()
+
+    // Scheduler to execute logic that will dump threads and heap
+    def scheduler = Executors.newSingleThreadScheduledExecutor({ r ->
+      Thread t = new Thread(r, "dump-scheduler")
+      t.setDaemon(true)
+      return t
+    })
+
+    // Schedule the dump job:
+    def future = scheduler.schedule({
+      try {
+        def threadDumpFile = new File(dupmsDir, "${System.currentTimeMillis()}-thread-dump.log")
+
+        new ProcessBuilder("jcmd", "0", "Thread.print", "-l")
+          .redirectErrorStream(true)
+          .redirectOutput(threadDumpFile)
+          .start().waitFor()
+
+        // Collect PIDs of all Java processes:
+        def jvmProcesses = "jcmd -l".execute().text.readLines()
+        jvmProcesses.each { p ->
+          // Process only test executors.
+          if (!p.contains("Gradle Test Executor")) {
+            return
+          }
+
+          def pid = p.substring(0, p.indexOf(' '))
+          def heapDumpFile = "${dupmsDir.absolutePath}/${System.currentTimeMillis()}-${pid}.hprof"
+          def cmd = "jcmd ${pid} GC.heap_dump ${heapDumpFile}"
+          cmd.execute().waitFor()
+        }
+      } catch (Throwable t) {
+        logger.warn("Dumping failed: ${t.message}", t)
+      } finally {
+        scheduler.shutdown()
+      }
+    }, 7, TimeUnit.MINUTES) // You can adjust this line with required delay.
+
+    // Store handles for cancellation in doLast:
+    ext.dumpFuture = future
+    ext.dumpScheduler = scheduler
+  }
+
+  doLast {
+    // Cancel if task completed faster than specified timeout.
+    try {
+      ext.dumpFuture?.cancel(false)
+    } finally {
+      ext.dumpScheduler?.shutdownNow()
+    }
+  }
+}