Fallback to itimer profiler mode inside containers

2 files changed, 48 insertions, 8 deletions

diff --git a/spark-common/src/main/java/me/lucko/spark/common/sampler/async/AsyncProfilerAccess.java b/spark-common/src/main/java/me/lucko/spark/common/sampler/async/AsyncProfilerAccess.java
index 06db795..3dfbbbf 100644
--- a/spark-common/src/main/java/me/lucko/spark/common/sampler/async/AsyncProfilerAccess.java
+++ b/spark-common/src/main/java/me/lucko/spark/common/sampler/async/AsyncProfilerAccess.java
@@ -45,22 +45,31 @@ public enum AsyncProfilerAccess {
     /** An instance of the async-profiler Java API. */
     private final AsyncProfiler profiler;
 
+    /** The event to use for profiling */
+    private final ProfilingEvent profilingEvent;
+
     /** If profiler is null, contains the reason why setup failed */
     private final Exception setupException;
 
     AsyncProfilerAccess() {
         AsyncProfiler profiler;
+        ProfilingEvent profilingEvent = null;
         Exception setupException = null;
 
         try {
             profiler = load();
-            ensureCpuEventSupported(profiler);
+            if (isEventSupported(profiler, ProfilingEvent.CPU, false)) {
+                profilingEvent = ProfilingEvent.CPU;
+            } else if (isEventSupported(profiler, ProfilingEvent.ITIMER, true)) {
+                profilingEvent = ProfilingEvent.ITIMER;
+            }
         } catch (Exception e) {
             profiler = null;
             setupException = e;
         }
 
         this.profiler = profiler;
+        this.profilingEvent = profilingEvent;
         this.setupException = setupException;
     }
 
@@ -71,11 +80,18 @@ public enum AsyncProfilerAccess {
         return this.profiler;
     }
 
+    public ProfilingEvent getProfilingEvent() {
+        return this.profilingEvent;
+    }
+
     public boolean checkSupported(SparkPlatform platform) {
         if (this.setupException != null) {
             if (this.setupException instanceof UnsupportedSystemException) {
                 platform.getPlugin().log(Level.INFO, "The async-profiler engine is not supported for your os/arch (" +
                         this.setupException.getMessage() + "), so the built-in Java engine will be used instead.");
+            } else if (this.setupException instanceof NativeLoadingException && this.setupException.getCause().getMessage().contains("libstdc++")) {
+                platform.getPlugin().log(Level.WARNING, "Unable to initialise the async-profiler engine because libstdc++ is not installed.");
+                platform.getPlugin().log(Level.WARNING, "Please see here for more information: https://spark.lucko.me/docs/misc/Using-async-profiler#install-libstdc");
             } else {
                 platform.getPlugin().log(Level.WARNING, "Unable to initialise the async-profiler engine: " + this.setupException.getMessage());
                 platform.getPlugin().log(Level.WARNING, "Please see here for more information: https://spark.lucko.me/docs/misc/Using-async-profiler");
@@ -118,7 +134,7 @@ public enum AsyncProfilerAccess {
         try {
             return AsyncProfiler.getInstance(extractPath.toAbsolutePath().toString());
         } catch (UnsatisfiedLinkError e) {
-            throw new RuntimeException("A runtime error occurred whilst loading the native library", e);
+            throw new NativeLoadingException(e);
         }
     }
 
@@ -126,12 +142,30 @@ public enum AsyncProfilerAccess {
      * Checks the {@code profiler} to ensure the CPU event is supported.
      *
      * @param profiler the profiler instance
-     * @throws Exception if the event is not supported
+     * @return if the event is supported
      */
-    private static void ensureCpuEventSupported(AsyncProfiler profiler) throws Exception {
-        String resp = profiler.execute("check,event=cpu").trim();
-        if (!resp.equalsIgnoreCase("ok")) {
-            throw new UnsupportedOperationException("CPU event is not supported");
+    private static boolean isEventSupported(AsyncProfiler profiler, ProfilingEvent event, boolean throwException) {
+        try {
+            String resp = profiler.execute("check,event=" + event).trim();
+            if (resp.equalsIgnoreCase("ok")) {
+                return true;
+            } else if (throwException) {
+                throw new IllegalArgumentException(resp);
+            }
+        } catch (Exception e) {
+            if (throwException) {
+                throw new RuntimeException("Event " + event + " is not supported", e);
+            }
+        }
+        return false;
+    }
+
+    enum ProfilingEvent {
+        CPU, ITIMER;
+
+        @Override
+        public String toString() {
+            return name().toLowerCase(Locale.ROOT);
         }
     }
 
@@ -140,4 +174,10 @@ public enum AsyncProfilerAccess {
             super(os + '/' + arch);
         }
     }
+
+    private static final class NativeLoadingException extends RuntimeException {
+        public NativeLoadingException(Throwable cause) {
+            super("A runtime error occurred whilst loading the native library", cause);
+        }
+    }
 }
diff --git a/spark-common/src/main/java/me/lucko/spark/common/sampler/async/AsyncSampler.java b/spark-common/src/main/java/me/lucko/spark/common/sampler/async/AsyncSampler.java
index 62325ae..5d587a0 100644
--- a/spark-common/src/main/java/me/lucko/spark/common/sampler/async/AsyncSampler.java
+++ b/spark-common/src/main/java/me/lucko/spark/common/sampler/async/AsyncSampler.java
@@ -99,7 +99,7 @@ public class AsyncSampler extends AbstractSampler {
             throw new RuntimeException("Unable to create temporary output file", e);
         }
 
-        String command = "start,event=cpu,interval=" + this.interval + "us,threads,jfr,file=" + this.outputFile.toString();
+        String command = "start,event=" + AsyncProfilerAccess.INSTANCE.getProfilingEvent() + ",interval=" + this.interval + "us,threads,jfr,file=" + this.outputFile.toString();
         if (this.threadDumper instanceof ThreadDumper.Specific) {
             command += ",filter";
         }