public void processTraces()

in apm-agent-plugins/apm-profiling-plugin/src/main/java/co/elastic/apm/agent/profiler/SamplingProfiler.java [503:566]
59 lines of code
14 McCabe index (conditional complexity)

    public void processTraces() throws IOException {
        if (jfrParser == null) {
            jfrParser = new JfrParser();
        }
        if (Thread.currentThread().isInterrupted()) {
            return;
        }
        createFilesIfRequired();

        long eof = startProcessingActivationEventsFile();
        if (eof == 0 && activationEventsBuffer.limit() == 0 && profiledThreads.isEmpty()) {
            logger.debug("No activation events during this period. Skip processing stack traces.");
            return;
        }
        long start = System.nanoTime();
        List<WildcardMatcher> excludedClasses = config.getExcludedClasses();
        List<WildcardMatcher> includedClasses = config.getIncludedClasses();
        if (config.isBackupDiagnosticFiles()) {
            backupDiagnosticFiles(eof);
        }
        try {
            jfrParser.parse(jfrFile, excludedClasses, includedClasses);
            final List<StackTraceEvent> stackTraceEvents = getSortedStackTraceEvents(jfrParser);
            if (logger.isDebugEnabled()) {
                logger.debug("Processing {} stack traces", stackTraceEvents.size());
            }
            List<StackFrame> stackFrames = new ArrayList<>();
            ElasticApmTracer tracer = this.tracer;
            ActivationEvent event = new ActivationEvent();
            long inferredSpansMinDuration = getInferredSpansMinDurationNs();
            for (StackTraceEvent stackTrace : stackTraceEvents) {
                processActivationEventsUpTo(stackTrace.nanoTime, event, eof);
                CallTree.Root root = profiledThreads.get(stackTrace.threadId);
                if (root != null) {
                    jfrParser.resolveStackTrace(stackTrace.stackTraceId, true, stackFrames, MAX_STACK_DEPTH);
                    if (stackFrames.size() == MAX_STACK_DEPTH) {
                        logger.debug("Max stack depth reached. Set profiling_included_classes or profiling_excluded_classes.");
                    }
                    // stack frames may not contain any Java frames
                    // see https://github.com/jvm-profiling-tools/async-profiler/issues/271#issuecomment-582430233
                    if (!stackFrames.isEmpty()) {
                        try {
                            root.addStackTrace(tracer, stackFrames, stackTrace.nanoTime, callTreePool, inferredSpansMinDuration);
                        } catch (Exception e) {
                            logger.warn("Removing call tree for thread {} because of exception while adding a stack trace: {} {}",
                                stackTrace.threadId, e.getClass(), e.getMessage());
                            logger.debug(e.getMessage(), e);
                            profiledThreads.remove(stackTrace.threadId);
                        }
                    }
                }
                stackFrames.clear();
            }
            // process all activation events that happened after the last stack trace event
            // otherwise we may miss root deactivations
            processActivationEventsUpTo(System.nanoTime(), event, eof);
        } finally {
            if (logger.isDebugEnabled()) {
                logger.debug("Processing traces took {}µs", (System.nanoTime() - start) / 1000);
            }
            jfrParser.resetState();
            resetActivationEventBuffer();
        }
    }