Add configuration option for liveheap subsampling (#7380)

Author: jbachorik

dd-java-agent/agent-profiling/profiling-ddprof/src/main/java/com/datadog/profiling/ddprof/DatadogProfiler.java

@@ -4,6 +4,7 @@
 import static com.datadog.profiling.ddprof.DatadogProfilerConfig.getCStack;
 import static com.datadog.profiling.ddprof.DatadogProfilerConfig.getContextAttributes;
 import static com.datadog.profiling.ddprof.DatadogProfilerConfig.getCpuInterval;
+import static com.datadog.profiling.ddprof.DatadogProfilerConfig.getLiveHeapSamplePercent;
 import static com.datadog.profiling.ddprof.DatadogProfilerConfig.getLogLevel;
 import static com.datadog.profiling.ddprof.DatadogProfilerConfig.getSafeMode;
 import static com.datadog.profiling.ddprof.DatadogProfilerConfig.getSchedulingEvent;
@@ -281,6 +282,8 @@ String cmdStartProfiling(Path file) throws IllegalStateException {
       }
       if (profilingModes.contains(MEMLEAK)) {
         cmd.append(isLiveHeapSizeTrackingEnabled(configProvider) ? 'L' : 'l');
+        cmd.append(':')
+            .append(String.format("%.2f", getLiveHeapSamplePercent(configProvider) / 100.0d));
       }
     }
     String cmdString = cmd.toString();

dd-java-agent/agent-profiling/profiling-ddprof/src/main/java/com/datadog/profiling/ddprof/DatadogProfilerConfig.java

@@ -22,6 +22,8 @@
 import static datadog.trace.api.config.ProfilingConfig.PROFILING_DATADOG_PROFILER_LIVEHEAP_ENABLED;
 import static datadog.trace.api.config.ProfilingConfig.PROFILING_DATADOG_PROFILER_LIVEHEAP_ENABLED_DEFAULT;
 import static datadog.trace.api.config.ProfilingConfig.PROFILING_DATADOG_PROFILER_LIVEHEAP_INTERVAL;
+import static datadog.trace.api.config.ProfilingConfig.PROFILING_DATADOG_PROFILER_LIVEHEAP_SAMPLE_PERCENT;
+import static datadog.trace.api.config.ProfilingConfig.PROFILING_DATADOG_PROFILER_LIVEHEAP_SAMPLE_PERCENT_DEFAULT;
 import static datadog.trace.api.config.ProfilingConfig.PROFILING_DATADOG_PROFILER_LIVEHEAP_TRACK_HEAPSIZE;
 import static datadog.trace.api.config.ProfilingConfig.PROFILING_DATADOG_PROFILER_LIVEHEAP_TRACK_HEAPSIZE_DEFAFULT;
 import static datadog.trace.api.config.ProfilingConfig.PROFILING_DATADOG_PROFILER_LOG_LEVEL;
@@ -224,6 +226,13 @@ public static boolean isLiveHeapSizeTrackingEnabled(ConfigProvider configProvide
         PROFILING_DATADOG_PROFILER_LIVEHEAP_TRACK_HEAPSIZE_DEFAFULT);
   }
 
+  public static int getLiveHeapSamplePercent(ConfigProvider configProvider) {
+    return getInteger(
+        configProvider,
+        PROFILING_DATADOG_PROFILER_LIVEHEAP_SAMPLE_PERCENT,
+        PROFILING_DATADOG_PROFILER_LIVEHEAP_SAMPLE_PERCENT_DEFAULT);
+  }
+
   public static long getMemleakInterval(ConfigProvider configProvider) {
     long maxheap = ManagementFactory.getMemoryMXBean().getHeapMemoryUsage().getMax();
     long memleakIntervalDefault =

dd-trace-api/src/main/java/datadog/trace/api/config/ProfilingConfig.java

@@ -162,6 +162,11 @@ public final class ProfilingConfig {
   public static final String PROFILING_DATADOG_PROFILER_LIVEHEAP_TRACK_HEAPSIZE =
       "profiling.ddprof.liveheap.track_size.enabled";
   public static final boolean PROFILING_DATADOG_PROFILER_LIVEHEAP_TRACK_HEAPSIZE_DEFAFULT = true;
+  public static final String PROFILING_DATADOG_PROFILER_LIVEHEAP_SAMPLE_PERCENT =
+      "profiling.ddprof.liveheap.sample_percent";
+  public static final int PROFILING_DATADOG_PROFILER_LIVEHEAP_SAMPLE_PERCENT_DEFAULT =
+      50; // default to 10% of allocation samples
+
   public static final String PROFILING_ENDPOINT_COLLECTION_ENABLED =
       "profiling.endpoint.collection.enabled";
   public static final boolean PROFILING_ENDPOINT_COLLECTION_ENABLED_DEFAULT = true;

gradle/libs.versions.toml

@@ -29,7 +29,7 @@ moshi = '1.11.0'
 testcontainers = '1.19.3'
 jmc = "8.1.0"
 autoservice = "1.0-rc7"
-ddprof = "1.9.0"
+ddprof = "1.12.0"
 asm = "9.7"
 cafe_crypto = "0.1.0"
 lz4 = "1.7.1"