Always use rate limiter for metadata requests, and sleep for a random amount of time between fetching metadata items.

src/main/java/org/qortal/api/resource/ArbitraryResource.java

@@ -724,7 +724,7 @@ public class ArbitraryResource {
 		ArbitraryDataResource resource = new ArbitraryDataResource(name, ResourceIdType.NAME, service, identifier);
 
 		try {
-			ArbitraryDataTransactionMetadata transactionMetadata = ArbitraryMetadataManager.getInstance().fetchMetadata(resource, false);
+			ArbitraryDataTransactionMetadata transactionMetadata = ArbitraryMetadataManager.getInstance().fetchMetadata(resource, true);
 			if (transactionMetadata != null) {
 				ArbitraryResourceMetadata resourceMetadata = ArbitraryResourceMetadata.fromTransactionMetadata(transactionMetadata, true);
 				if (resourceMetadata != null) {

src/main/java/org/qortal/controller/arbitrary/ArbitraryDataManager.java

@@ -275,7 +275,10 @@ public class ArbitraryDataManager extends Thread {
 		int offset = 0;
 
 		while (!isStopping) {
-			Thread.sleep(1000L);
+			final int minSeconds = 3;
+			final int maxSeconds = 10;
+			final int randomSleepTime = new Random().nextInt((maxSeconds - minSeconds + 1)) + minSeconds;
+			Thread.sleep(randomSleepTime * 1000L);
 
 			// Any arbitrary transactions we want to fetch data for?
 			try (final Repository repository = RepositoryManager.getRepository()) {