Add the high-contention warning

If the number of serialization-related retry is greater than predefined
value (currently 8) a warning is issued instead of the usual debug
message. This is to tell administrator that something wrong - i.e. high
contention - is occurring.

repo/repo-sql-impl/src/main/java/com/evolveum/midpoint/repo/sql/SqlRepositoryServiceImpl.java

@@ -104,6 +104,7 @@ public class SqlRepositoryServiceImpl extends SqlBaseService implements Reposito
     public static final String PERFORMANCE_LOG_NAME = SqlRepositoryServiceImpl.class.getName() + ".performance";
     public static final String CONTENTION_LOG_NAME = SqlRepositoryServiceImpl.class.getName() + ".contention";
     public static final int CONTENTION_LOG_DEBUG_THRESHOLD = 3;
+    public static final int MAIN_LOG_WARN_THRESHOLD = 8;
 
     private static final Trace LOGGER = TraceManager.getTrace(SqlRepositoryServiceImpl.class);
     private static final Trace LOGGER_PERFORMANCE = TraceManager.getTrace(PERFORMANCE_LOG_NAME);

repo/repo-sql-impl/src/main/java/com/evolveum/midpoint/repo/sql/helpers/BaseHelper.java

@@ -216,7 +216,11 @@ public int logOperationAttempt(String oid, String operation, int attempt, @NotNu
 		} else {
 			CONTENTION_LOGGER.trace(message, objects);
 		}
-		LOGGER.debug(message, objects);
+		if (attempt >= SqlRepositoryServiceImpl.MAIN_LOG_WARN_THRESHOLD) {
+			LOGGER.warn(message, objects);
+		} else {
+			LOGGER.debug(message, objects);
+		}
 		if (waitTime > 0) {
 			try {
 				Thread.sleep(waitTime);