test/hotspot/jtreg/runtime/appcds/TestCommon.java

*** 143,152 ****
--- 143,161 ----
          String[] cmdLine = cmd.toArray(new String[cmd.size()]);
          ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(true, cmdLine);
          return executeAndLog(pb, "dump");
      }
  
+     // This allows you to run the AppCDS tests with JFR enabled at runtime (though not at
+     // dump time, as that's uncommon for typical AppCDS users).
+     //
+     // To run in this special mode, specify the following in your jtreg command-line
+     //    -vmoptions:-Dtest.cds.run.with.jfr=true
+     //
+     // Some AppCDS tests are not compatible with this mode. See the group
+     // hotspot_appcds_with_jfr in ../../TEST.ROOT for details.
+     private static final boolean RUN_WITH_JFR = Boolean.getBoolean("test.cds.run.with.jfr");
  
      // Execute JVM using AppCDS archive with specified AppCDSOptions
      public static OutputAnalyzer runWithArchive(AppCDSOptions opts)
          throws Exception {
  
*** 164,173 ****
--- 173,198 ----
              cmd.add(opts.appJar);
          }
  
          for (String s : opts.suffix) cmd.add(s);
  
+         if (RUN_WITH_JFR) {
+             boolean usesJFR = false;
+             for (String s : cmd) {
+                 if (s.startsWith("-XX:StartFlightRecording=") || s.startsWith("-XX:FlightRecorderOptions")) {
+                     System.out.println("JFR option might have been specified. Don't interfere: " + s);
+                     usesJFR = true;
+                     break;
+                 }
+             }
+             if (!usesJFR) {
+                 System.out.println("JFR option not specified. Enabling JFR ...");
+                 cmd.add(0, "-XX:StartFlightRecording=dumponexit=true");
+                 System.out.println(cmd);
+             }
+         }
+ 
          String[] cmdLine = cmd.toArray(new String[cmd.size()]);
          ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(true, cmdLine);
          return executeAndLog(pb, "exec");
      }