code: public static JobManagerSharedServices fromConfiguration(
  			Configuration config,
  			BlobServer blobServer) throws Exception {
  
  		checkNotNull(config);
  		checkNotNull(blobServer);
  
  		final String classLoaderResolveOrder =
  			config.getString(CoreOptions.CLASSLOADER_RESOLVE_ORDER);
  
  		final String[] alwaysParentFirstLoaderPatterns = CoreOptions.getParentFirstLoaderPatterns(config);
  
  		final BlobLibraryCacheManager libraryCacheManager =
  			new BlobLibraryCacheManager(
  				blobServer,
  				FlinkUserCodeClassLoaders.ResolveOrder.fromString(classLoaderResolveOrder),
  				alwaysParentFirstLoaderPatterns);
  
  		final FiniteDuration timeout;
  		try {
  			timeout = AkkaUtils.getTimeout(config);
  		} catch (NumberFormatException e) {
  			throw new IllegalConfigurationException(AkkaUtils.formatDurationParsingErrorMessage());
  		}
  
  		final ScheduledExecutorService futureExecutor = Executors.newScheduledThreadPool(
  				Hardware.getNumberCPUCores(),
  				new ExecutorThreadFactory("jobmanager-future"));
  
  		final StackTraceSampleCoordinator stackTraceSampleCoordinator =
  			new StackTraceSampleCoordinator(futureExecutor, timeout.toMillis());
  		final int cleanUpInterval = config.getInteger(WebOptions.BACKPRESSURE_CLEANUP_INTERVAL);
  		final BackPressureStatsTrackerImpl backPressureStatsTracker = new BackPressureStatsTrackerImpl(
  			stackTraceSampleCoordinator,
  			cleanUpInterval,
  			config.getInteger(WebOptions.BACKPRESSURE_NUM_SAMPLES),
  			config.getInteger(WebOptions.BACKPRESSURE_REFRESH_INTERVAL),
  			Time.milliseconds(config.getInteger(WebOptions.BACKPRESSURE_DELAY)));
  
  		futureExecutor.scheduleWithFixedDelay(
  			backPressureStatsTracker::cleanUpOperatorStatsCache,
  			cleanUpInterval,
  			cleanUpInterval,
  			TimeUnit.MILLISECONDS);
  
  		return new JobManagerSharedServices(
  			futureExecutor,
  			libraryCacheManager,
  			RestartStrategyFactory.createRestartStrategyFactory(config),
  			stackTraceSampleCoordinator,
  			backPressureStatsTracker,
  			blobServer);
  	}
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