Performance enhancements to the JPA server and better retry logic in

$trigger-subscription

hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/config/BaseConfig.java

@@ -104,8 +104,30 @@ public abstract class BaseConfig implements SchedulingConfigurer {
 					retVal.put(AvailableSettings.CONNECTION_HANDLING, PhysicalConnectionHandlingMode.DELAYED_ACQUISITION_AND_HOLD);
 				}
 
+				/*
+				 * Set some performance options
+				 */
+
+				if (!retVal.containsKey(AvailableSettings.STATEMENT_BATCH_SIZE)) {
+					retVal.put(AvailableSettings.STATEMENT_BATCH_SIZE, "30");
+				}
+
+				if (!retVal.containsKey(AvailableSettings.ORDER_INSERTS)) {
+					retVal.put(AvailableSettings.ORDER_INSERTS, "true");
+				}
+
+				if (!retVal.containsKey(AvailableSettings.ORDER_UPDATES)) {
+					retVal.put(AvailableSettings.ORDER_UPDATES, "true");
+				}
+
+				if (!retVal.containsKey(AvailableSettings.BATCH_VERSIONED_DATA)) {
+					retVal.put(AvailableSettings.BATCH_VERSIONED_DATA, "true");
+				}
+
 				return retVal;
 			}
+
+
 		};
 		configureEntityManagerFactory(retVal, fhirContext());
 		return retVal;

hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/dao/SearchBuilder.java

@@ -64,7 +64,6 @@ import org.hibernate.ScrollableResults;
 import org.hibernate.query.Query;
 import org.hibernate.query.criteria.internal.CriteriaBuilderImpl;
 import org.hibernate.query.criteria.internal.predicate.BooleanStaticAssertionPredicate;
-import org.hl7.fhir.dstu3.model.BaseResource;
 import org.hl7.fhir.instance.model.api.IAnyResource;
 import org.hl7.fhir.instance.model.api.IBaseResource;
 import org.hl7.fhir.instance.model.api.IIdType;
@@ -88,7 +87,7 @@ import static org.apache.commons.lang3.StringUtils.*;
 @SuppressWarnings("JpaQlInspection")
 public class SearchBuilder implements ISearchBuilder {
 
-	private static final List<Long> EMPTY_LONG_LIST = Collections.unmodifiableList(new ArrayList<Long>());
+	private static final List<Long> EMPTY_LONG_LIST = Collections.unmodifiableList(new ArrayList<>());
 	private static final org.slf4j.Logger ourLog = org.slf4j.LoggerFactory.getLogger(SearchBuilder.class);
 	private static Long NO_MORE = -1L;
 	private static HandlerTypeEnum ourLastHandlerMechanismForUnitTest;
@@ -96,7 +95,7 @@ public class SearchBuilder implements ISearchBuilder {
 	private static String ourLastHandlerThreadForUnitTest;
 	private static boolean ourTrackHandlersForUnitTest;
 	protected IResourceTagDao myResourceTagDao;
-	protected IResourceSearchViewDao myResourceSearchViewDao;
+	private IResourceSearchViewDao myResourceSearchViewDao;
 	private List<Long> myAlsoIncludePids;
 	private CriteriaBuilder myBuilder;
 	private BaseHapiFhirDao<?> myCallingDao;
@@ -122,7 +121,7 @@ public class SearchBuilder implements ISearchBuilder {
 	/**
 	 * Constructor
 	 */
-	public SearchBuilder(FhirContext theFhirContext, EntityManager theEntityManager,
+	SearchBuilder(FhirContext theFhirContext, EntityManager theEntityManager,
 					  IFulltextSearchSvc theFulltextSearchSvc, BaseHapiFhirDao<?> theDao,
 					  IResourceIndexedSearchParamUriDao theResourceIndexedSearchParamUriDao, IForcedIdDao theForcedIdDao,
 					  IHapiTerminologySvc theTerminologySvc, ISearchParamRegistry theSearchParamRegistry,
@@ -175,8 +174,7 @@ public class SearchBuilder implements ISearchBuilder {
 
 		List<Predicate> codePredicates = new ArrayList<>();
 		for (IQueryParameterType nextOr : theList) {
-			IQueryParameterType params = nextOr;
+			Predicate p = createPredicateDate(nextOr, theResourceName, theParamName, myBuilder, join);
-			Predicate p = createPredicateDate(params, theResourceName, theParamName, myBuilder, join);
 			codePredicates.add(p);
 		}
 
@@ -216,6 +214,7 @@ public class SearchBuilder implements ISearchBuilder {
 				throw new InvalidRequestException("Invalid resource type: " + targetResourceType);
 			}
 
+			assert parameterName != null;
 			String paramName = parameterName.replaceAll("\\..*", "");
 			RuntimeSearchParam owningParameterDef = myCallingDao.getSearchParamByName(targetResourceDefinition, paramName);
 			if (owningParameterDef == null) {
@@ -244,7 +243,7 @@ public class SearchBuilder implements ISearchBuilder {
 	private void addPredicateLanguage(List<List<? extends IQueryParameterType>> theList) {
 		for (List<? extends IQueryParameterType> nextList : theList) {
 
-			Set<String> values = new HashSet<String>();
+			Set<String> values = new HashSet<>();
 			for (IQueryParameterType next : nextList) {
 				if (next instanceof StringParam) {
 					String nextValue = ((StringParam) next).getValue();
@@ -265,7 +264,6 @@ public class SearchBuilder implements ISearchBuilder {
 			myPredicates.add(predicate);
 		}
 
-		return;
 	}
 
 	private void addPredicateNumber(String theResourceName, String theParamName, List<? extends IQueryParameterType> theList) {
@@ -279,10 +277,9 @@ public class SearchBuilder implements ISearchBuilder {
 
 		List<Predicate> codePredicates = new ArrayList<>();
 		for (IQueryParameterType nextOr : theList) {
-			IQueryParameterType params = nextOr;
 
-			if (params instanceof NumberParam) {
+			if (nextOr instanceof NumberParam) {
-				NumberParam param = (NumberParam) params;
+				NumberParam param = (NumberParam) nextOr;
 
 				BigDecimal value = param.getValue();
 				if (value == null) {
@@ -293,12 +290,12 @@ public class SearchBuilder implements ISearchBuilder {
 				ParamPrefixEnum prefix = ObjectUtils.defaultIfNull(param.getPrefix(), ParamPrefixEnum.EQUAL);
 				String invalidMessageName = "invalidNumberPrefix";
 
-				Predicate predicateNumeric = createPredicateNumeric(theResourceName, theParamName, join, myBuilder, params, prefix, value, fromObj, invalidMessageName);
+				Predicate predicateNumeric = createPredicateNumeric(theResourceName, theParamName, join, myBuilder, nextOr, prefix, value, fromObj, invalidMessageName);
 				Predicate predicateOuter = combineParamIndexPredicateWithParamNamePredicate(theResourceName, theParamName, join, predicateNumeric);
 				codePredicates.add(predicateOuter);
 
 			} else {
-				throw new IllegalArgumentException("Invalid token type: " + params.getClass());
+				throw new IllegalArgumentException("Invalid token type: " + nextOr.getClass());
 			}
 
 		}
@@ -392,7 +389,7 @@ public class SearchBuilder implements ISearchBuilder {
 
 					final List<Class<? extends IBaseResource>> resourceTypes;
 					String resourceId;
-					if (!ref.getValue().matches("[a-zA-Z]+\\/.*")) {
+					if (!ref.getValue().matches("[a-zA-Z]+/.*")) {
 
 						RuntimeSearchParam param = mySearchParamRegistry.getActiveSearchParam(theResourceName, theParamName);
 						resourceTypes = new ArrayList<>();
@@ -904,6 +901,7 @@ public class SearchBuilder implements ISearchBuilder {
 			case NUMBER:
 			case REFERENCE:
 			case URI:
+			case SPECIAL:
 				break;
 		}
 
@@ -1590,6 +1588,7 @@ public class SearchBuilder implements ISearchBuilder {
 				sortAttrName = new String[]{"myValue"};
 				joinType = JoinEnum.QUANTITY;
 				break;
+			case SPECIAL:
 			case COMPOSITE:
 			case HAS:
 			default:
@@ -2022,6 +2021,7 @@ public class SearchBuilder implements ISearchBuilder {
 						}
 						break;
 					case HAS:
+					case SPECIAL:
 						// should not happen
 						break;
 				}
@@ -2076,6 +2076,7 @@ public class SearchBuilder implements ISearchBuilder {
 			case REFERENCE:
 				qp = new ReferenceParam();
 				break;
+			case SPECIAL:
 			case URI:
 			case HAS:
 			default:
@@ -2114,7 +2115,7 @@ public class SearchBuilder implements ISearchBuilder {
 		private Long myNext;
 		private int myPageSize = myCallingDao.getConfig().getEverythingIncludesFetchPageSize();
 
-		public IncludesIterator(Set<Long> thePidSet) {
+		IncludesIterator(Set<Long> thePidSet) {
 			myCurrentPids = new ArrayList<>(thePidSet);
 			myCurrentIterator = EMPTY_LONG_LIST.iterator();
 			myCurrentOffset = 0;
@@ -2128,7 +2129,6 @@ public class SearchBuilder implements ISearchBuilder {
 					break;
 				}
 
-				if (!myCurrentIterator.hasNext()) {
 				int start = myCurrentOffset;
 				int end = myCurrentOffset + myPageSize;
 				if (end > myCurrentPids.size()) {
@@ -2143,7 +2143,6 @@ public class SearchBuilder implements ISearchBuilder {
 				Set<Include> includes = Collections.singleton(new Include("*", true));
 				Set<Long> newPids = loadIncludes(myCallingDao, myContext, myEntityManager, pidsToScan, includes, false, myParams.getLastUpdated());
 				myCurrentIterator = newPids.iterator();
-				}
 
 			}
 		}
@@ -2151,7 +2150,7 @@ public class SearchBuilder implements ISearchBuilder {
 		@Override
 		public boolean hasNext() {
 			fetchNext();
-			return myNext != NO_MORE;
+			return !NO_MORE.equals(myNext);
 		}
 
 		@Override
@@ -2268,7 +2267,7 @@ public class SearchBuilder implements ISearchBuilder {
 				myFirst = false;
 			}
 
-			if (myNext == NO_MORE) {
+			if (NO_MORE.equals(myNext)) {
 				ourLog.debug("Query found {} matches in {}ms for query {}", myPidSet.size(), myStopwatch.getMillis(), mySearchUuid);
 			}
 
@@ -2279,7 +2278,7 @@ public class SearchBuilder implements ISearchBuilder {
 			if (myNext == null) {
 				fetchNext();
 			}
-			return myNext != NO_MORE;
+			return !NO_MORE.equals(myNext);
 		}
 
 		@Override
@@ -2287,7 +2286,7 @@ public class SearchBuilder implements ISearchBuilder {
 			fetchNext();
 			Long retVal = myNext;
 			myNext = null;
-			Validate.isTrue(retVal != NO_MORE, "No more elements");
+			Validate.isTrue(!NO_MORE.equals(retVal), "No more elements");
 			return retVal;
 		}
 
@@ -2301,7 +2300,7 @@ public class SearchBuilder implements ISearchBuilder {
 		private final Set<String> myUniqueQueryStrings;
 		private Iterator<Long> myWrap = null;
 
-		public UniqueIndexIterator(Set<String> theUniqueQueryStrings) {
+		UniqueIndexIterator(Set<String> theUniqueQueryStrings) {
 			myUniqueQueryStrings = theUniqueQueryStrings;
 		}
 
@@ -2343,7 +2342,7 @@ public class SearchBuilder implements ISearchBuilder {
 		private boolean myCountLoaded;
 		private Long myCount;
 
-		public CountQueryIterator(TypedQuery<Long> theQuery) {
+		CountQueryIterator(TypedQuery<Long> theQuery) {
 			myQuery = theQuery;
 		}
 
@@ -2374,7 +2373,7 @@ public class SearchBuilder implements ISearchBuilder {
 		private final JoinEnum myJoinType;
 		private final String myParamName;
 
-		public JoinKey(String theParamName, JoinEnum theJoinType) {
+		JoinKey(String theParamName, JoinEnum theJoinType) {
 			super();
 			myParamName = theParamName;
 			myJoinType = theJoinType;
@@ -2382,6 +2381,9 @@ public class SearchBuilder implements ISearchBuilder {
 
 		@Override
 		public boolean equals(Object theObj) {
+			if (!(theObj instanceof JoinKey)) {
+				return false;
+			}
 			JoinKey obj = (JoinKey) theObj;
 			return new EqualsBuilder()
 				.append(myParamName, obj.myParamName)
@@ -2482,8 +2484,7 @@ public class SearchBuilder implements ISearchBuilder {
 		cq.where(SearchBuilder.toArray(lastUpdatedPredicates));
 		TypedQuery<Long> query = theEntityManager.createQuery(cq);
 
-		List<Long> resultList = query.getResultList();
+		return query.getResultList();
-		return resultList;
 	}
 
 	@VisibleForTesting
@@ -2504,8 +2505,8 @@ public class SearchBuilder implements ISearchBuilder {
 		ourTrackHandlersForUnitTest = true;
 	}
 
-	static Predicate[] toArray(List<Predicate> thePredicates) {
+	private static Predicate[] toArray(List<Predicate> thePredicates) {
-		return thePredicates.toArray(new Predicate[thePredicates.size()]);
+		return thePredicates.toArray(new Predicate[0]);
 	}
 
 }

hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/provider/SubscriptionTriggeringProvider.java

@@ -46,7 +46,9 @@ import ca.uhn.fhir.util.StopWatch;
 import ca.uhn.fhir.util.ValidateUtil;
 import org.apache.commons.lang3.ObjectUtils;
 import org.apache.commons.lang3.Validate;
+import org.apache.commons.lang3.concurrent.BasicThreadFactory;
 import org.apache.commons.lang3.time.DateUtils;
+import org.apache.commons.lang3.tuple.Pair;
 import org.hl7.fhir.instance.model.IdType;
 import org.hl7.fhir.instance.model.api.IBaseParameters;
 import org.hl7.fhir.instance.model.api.IBaseResource;
@@ -62,7 +64,7 @@ import org.springframework.scheduling.annotation.Scheduled;
 
 import javax.annotation.PostConstruct;
 import java.util.*;
-import java.util.concurrent.TimeUnit;
+import java.util.concurrent.*;
 import java.util.stream.Collectors;
 
 import static org.apache.commons.lang3.StringUtils.isBlank;
@@ -84,6 +86,7 @@ public class SubscriptionTriggeringProvider implements IResourceProvider, Applic
 	@Autowired
 	private ISearchCoordinatorSvc mySearchCoordinatorSvc;
 	private ApplicationContext myAppCtx;
+	private ExecutorService myExecutorService;
 
 	/**
 	 * Sets the maximum number of resources that will be submitted in a single pass
@@ -105,6 +108,37 @@ public class SubscriptionTriggeringProvider implements IResourceProvider, Applic
 		Collection values1 = myAppCtx.getBeansOfType(BaseSubscriptionInterceptor.class).values();
 		Collection<BaseSubscriptionInterceptor<?>> values = (Collection<BaseSubscriptionInterceptor<?>>) values1;
 		mySubscriptionInterceptorList.addAll(values);
+
+
+		LinkedBlockingQueue<Runnable> executorQueue = new LinkedBlockingQueue<>(1000);
+		BasicThreadFactory threadFactory = new BasicThreadFactory.Builder()
+			.namingPattern("SubscriptionTriggering-%d")
+			.daemon(false)
+			.priority(Thread.NORM_PRIORITY)
+			.build();
+		RejectedExecutionHandler rejectedExecutionHandler = new RejectedExecutionHandler() {
+			@Override
+			public void rejectedExecution(Runnable theRunnable, ThreadPoolExecutor theExecutor) {
+				ourLog.info("Note: Subscription triggering queue is full ({} elements), waiting for a slot to become available!", executorQueue.size());
+				StopWatch sw = new StopWatch();
+				try {
+					executorQueue.put(theRunnable);
+				} catch (InterruptedException theE) {
+					throw new RejectedExecutionException("Task " + theRunnable.toString() +
+						" rejected from " + theE.toString());
+				}
+				ourLog.info("Slot become available after {}ms", sw.getMillis());
+			}
+		};
+		myExecutorService = new ThreadPoolExecutor(
+			0,
+			10,
+			0L,
+			TimeUnit.MILLISECONDS,
+			executorQueue,
+			threadFactory,
+			rejectedExecutionHandler);
+
 	}
 
 	@Operation(name = JpaConstants.OPERATION_TRIGGER_SUBSCRIPTION)
@@ -227,10 +261,17 @@ public class SubscriptionTriggeringProvider implements IResourceProvider, Applic
 
 		// Submit individual resources
 		int totalSubmitted = 0;
+		List<Pair<String, Future<Void>>> futures = new ArrayList<>();
 		while (theJobDetails.getRemainingResourceIds().size() > 0 && totalSubmitted < myMaxSubmitPerPass) {
 			totalSubmitted++;
 			String nextResourceId = theJobDetails.getRemainingResourceIds().remove(0);
-			submitResource(theJobDetails.getSubscriptionId(), nextResourceId);
+			Future<Void> future = submitResource(theJobDetails.getSubscriptionId(), nextResourceId);
+			futures.add(Pair.of(nextResourceId, future));
+		}
+
+		// Make sure these all succeeded in submitting
+		if (validateFuturesAndReturnTrueIfWeShouldAbort(futures)) {
+			return;
 		}
 
 		// If we don't have an active search started, and one needs to be.. start it
@@ -267,14 +308,22 @@ public class SubscriptionTriggeringProvider implements IResourceProvider, Applic
 			List<Long> resourceIds = mySearchCoordinatorSvc.getResources(theJobDetails.getCurrentSearchUuid(), fromIndex, toIndex);
 
 			ourLog.info("Triggering job[{}] delivering {} resources", theJobDetails.getJobId(), theJobDetails.getCurrentSearchUuid(), fromIndex, toIndex);
+			int highestIndexSubmitted = theJobDetails.getCurrentSearchLastUploadedIndex();
+
 			for (Long next : resourceIds) {
 				IBaseResource nextResource = resourceDao.readByPid(next);
-				submitResource(theJobDetails.getSubscriptionId(), nextResource);
+				Future<Void> future = submitResource(theJobDetails.getSubscriptionId(), nextResource);
+				futures.add(Pair.of(nextResource.getIdElement().getIdPart(), future));
 				totalSubmitted++;
-				theJobDetails.setCurrentSearchLastUploadedIndex(theJobDetails.getCurrentSearchLastUploadedIndex()+1);
+				highestIndexSubmitted++;
 			}
 
-			int expectedCount = toIndex - fromIndex;
+			if (validateFuturesAndReturnTrueIfWeShouldAbort(futures)) {
+				return;
+			}
+
+			theJobDetails.setCurrentSearchLastUploadedIndex(highestIndexSubmitted);
+
 			if (resourceIds.size() == 0 || (theJobDetails.getCurrentSearchCount() != null && toIndex >= theJobDetails.getCurrentSearchCount())) {
 				ourLog.info("Triggering job[{}] search {} has completed ", theJobDetails.getJobId(), theJobDetails.getCurrentSearchUuid());
 				theJobDetails.setCurrentSearchResourceType(null);
@@ -287,15 +336,34 @@ public class SubscriptionTriggeringProvider implements IResourceProvider, Applic
 		ourLog.info("Subscription trigger job[{}] triggered {} resources in {}ms ({} res / second)", theJobDetails.getJobId(), totalSubmitted, sw.getMillis(), sw.getThroughput(totalSubmitted, TimeUnit.SECONDS));
 	}
 
-	private void submitResource(String theSubscriptionId, String theResourceIdToTrigger) {
+	private boolean validateFuturesAndReturnTrueIfWeShouldAbort(List<Pair<String, Future<Void>>> theIdToFutures) {
+
+		for (Pair<String, Future<Void>> next : theIdToFutures) {
+			String nextDeliveredId = next.getKey();
+			try {
+				Future<Void> nextFuture = next.getValue();
+				nextFuture.get();
+				ourLog.info("Finished redelivering {}", nextDeliveredId);
+			} catch (Exception e) {
+				ourLog.error("Failure triggering resource " + nextDeliveredId, e);
+				return true;
+			}
+		}
+
+		// Clear the list since it will potentially get reused
+		theIdToFutures.clear();
+		return false;
+	}
+
+	private Future<Void> submitResource(String theSubscriptionId, String theResourceIdToTrigger) {
 		org.hl7.fhir.r4.model.IdType resourceId = new org.hl7.fhir.r4.model.IdType(theResourceIdToTrigger);
 		IFhirResourceDao<? extends IBaseResource> dao = myDaoRegistry.getResourceDao(resourceId.getResourceType());
 		IBaseResource resourceToTrigger = dao.read(resourceId);
 
-		submitResource(theSubscriptionId, resourceToTrigger);
+		return submitResource(theSubscriptionId, resourceToTrigger);
 	}
 
-	private void submitResource(String theSubscriptionId, IBaseResource theResourceToTrigger) {
+	private Future<Void> submitResource(String theSubscriptionId, IBaseResource theResourceToTrigger) {
 
 		ourLog.info("Submitting resource {} to subscription {}", theResourceToTrigger.getIdElement().toUnqualifiedVersionless().getValue(), theSubscriptionId);
 
@@ -305,9 +373,13 @@ public class SubscriptionTriggeringProvider implements IResourceProvider, Applic
 		msg.setSubscriptionId(new IdType(theSubscriptionId).toUnqualifiedVersionless().getValue());
 		msg.setNewPayload(myFhirContext, theResourceToTrigger);
 
+		return myExecutorService.submit(()->{
 			for (BaseSubscriptionInterceptor<?> next : mySubscriptionInterceptorList) {
 				next.submitResourceModified(msg);
 			}
+			return null;
+		});
+
 	}
 
 	public void cancelAll() {

hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/subscription/resthook/SubscriptionRestHookInterceptor.java

@@ -34,8 +34,6 @@ public class SubscriptionRestHookInterceptor extends BaseSubscriptionInterceptor
 	@Override
 	protected Optional<MessageHandler> createDeliveryHandler(CanonicalSubscription theSubscription) {
 		SubscriptionDeliveringRestHookSubscriber value = new SubscriptionDeliveringRestHookSubscriber(getSubscriptionDao(), getChannelType(), this);
-		// FIXME: remove
-		ourLog.info("** Creating delivery subscriber " + value + " for " + theSubscription.getIdElementString());
 		return Optional.of(value);
 	}
 

hapi-fhir-jpaserver-base/src/test/java/ca/uhn/fhir/jpa/config/TestR4Config.java

@@ -105,7 +105,7 @@ public class TestR4Config extends BaseJavaConfigR4 {
 
 		DataSource dataSource = ProxyDataSourceBuilder
 			.create(retVal)
-//			.logQueryBySlf4j(SLF4JLogLevel.INFO, "SQL")
+			.logQueryBySlf4j(SLF4JLogLevel.INFO, "SQL")
 			.logSlowQueryBySlf4j(10, TimeUnit.SECONDS)
 			.countQuery(new ThreadQueryCountHolder())
 			.build();
@@ -125,7 +125,6 @@ public class TestR4Config extends BaseJavaConfigR4 {
 
 	private Properties jpaProperties() {
 		Properties extraProperties = new Properties();
-		extraProperties.put("hibernate.jdbc.batch_size", "1");
 		extraProperties.put("hibernate.format_sql", "false");
 		extraProperties.put("hibernate.show_sql", "false");
 		extraProperties.put("hibernate.hbm2ddl.auto", "update");

hapi-fhir-jpaserver-base/src/test/java/ca/uhn/fhir/jpa/dao/r4/FhirResourceDaoR4CreateTest.java

@@ -4,6 +4,7 @@ import ca.uhn.fhir.jpa.dao.DaoConfig;
 import ca.uhn.fhir.jpa.dao.SearchParameterMap;
 import ca.uhn.fhir.rest.param.StringParam;
 import ca.uhn.fhir.util.TestUtil;
+import net.ttddyy.dsproxy.listener.ThreadQueryCountHolder;
 import org.hl7.fhir.instance.model.api.IIdType;
 import org.hl7.fhir.r4.model.Bundle;
 import org.hl7.fhir.r4.model.IdType;
@@ -109,6 +110,26 @@ public class FhirResourceDaoR4CreateTest extends BaseJpaR4Test {
 		assertThat(output.getEntry().get(1).getResponse().getLocation(), matchesPattern("Patient/[a-z0-9]{8}-.*"));
 
 
+	}
+
+	@Test
+	public void testWritesPerformMinimalSqlStatements() {
+		Patient p = new Patient();
+		p.addIdentifier().setSystem("sys1").setValue("val1");
+		p.addIdentifier().setSystem("sys2").setValue("val2");
+
+		ourLog.info("** About to perform write");
+		new ThreadQueryCountHolder().getOrCreateQueryCount("").setInsert(0);
+		new ThreadQueryCountHolder().getOrCreateQueryCount("").setUpdate(0);
+
+		myPatientDao.create(p);
+
+		ourLog.info("** Done performing write");
+
+		ourLog.info("Inserts: {}", new ThreadQueryCountHolder().getOrCreateQueryCount("").getInsert());
+		ourLog.info("Updates: {}", new ThreadQueryCountHolder().getOrCreateQueryCount("").getUpdate());
+
+
 	}
 
 

src/changes/changes.xml

@@ -105,6 +105,17 @@
 				batch operation. As of this version, when authorizing a transaction operation
 				(via the transaction() rule), both batch and transaction will be allowed.
 			</action>
+			<action type="add">
+				The JPA server now automatically supplies several appropriate hibernate performance
+				settings as long as the JPA EntityManagerFactory was created using HAPI FHIR's
+				built-in method for creating it.
+				<![CDATA[<br/><br/>]]>
+				Existing JPA projects should consider using 
+				<![CDATA[<code>super.entityManagerFactory()</code>]]>
+				as shown in
+				<![CDATA[<a href="https://github.com/hapifhir/hapi-fhir-jpaserver-starter/blob/master/src/main/java/ca/uhn/fhir/jpa/demo/FhirServerConfig.java#L62">the example project</a>]]>
+				if they are not already.
+			</action>
 		</release>
 
 		<release version="3.5.0" date="2018-09-17">