diff --git a/src/Model/Contact.php b/src/Model/Contact.php
index 428bc3684e..74a9619c2f 100644
--- a/src/Model/Contact.php
+++ b/src/Model/Contact.php
@@ -91,6 +91,8 @@ class Contact
 	 * @}
 	 */
 
+	const LOCK_INSERT = 'contact-insert';
+
 	/**
 	 * Account types
 	 *
@@ -1125,19 +1127,23 @@ class Contact
 			$condition = ['nurl' => Strings::normaliseLink($data["url"]), 'uid' => $uid, 'deleted' => false];
 
 			// Before inserting we do check if the entry does exist now.
-			DBA::lock('contact');
-			$contact = DBA::selectFirst('contact', ['id'], $condition, ['order' => ['id']]);
-			if (DBA::isResult($contact)) {
-				$contact_id = $contact['id'];
-				Logger::notice('Contact had been created (shortly) before', ['id' => $contact_id, 'url' => $url, 'uid' => $uid]);
-			} else {
-				DBA::insert('contact', $fields);
-				$contact_id = DBA::lastInsertId();
-				if ($contact_id) {
-					Logger::info('Contact inserted', ['id' => $contact_id, 'url' => $url, 'uid' => $uid]);
+			if (DI::lock()->acquire(self::LOCK_INSERT, 0)) {
+				$contact = DBA::selectFirst('contact', ['id'], $condition, ['order' => ['id']]);
+				if (DBA::isResult($contact)) {
+					$contact_id = $contact['id'];
+					Logger::notice('Contact had been created (shortly) before', ['id' => $contact_id, 'url' => $url, 'uid' => $uid]);
+				} else {
+					DBA::insert('contact', $fields);
+					$contact_id = DBA::lastInsertId();
+					if ($contact_id) {
+						Logger::info('Contact inserted', ['id' => $contact_id, 'url' => $url, 'uid' => $uid]);
+					}
 				}
+				DI::lock()->release(self::LOCK_INSERT);
+			} else {
+				Logger::warning('Contact lock had not been acquired');
 			}
-			DBA::unlock();
+
 			if (!$contact_id) {
 				Logger::info('Contact was not inserted', ['url' => $url, 'uid' => $uid]);
 				return 0;
diff --git a/src/Model/Item.php b/src/Model/Item.php
index a282762135..46d28ee822 100644
--- a/src/Model/Item.php
+++ b/src/Model/Item.php
@@ -71,6 +71,8 @@ class Item
 	const PT_FETCHED = 75;
 	const PT_PERSONAL_NOTE = 128;
 
+	const LOCK_INSERT = 'item-insert';
+
 	// Field list that is used to display the items
 	const DISPLAY_FIELDLIST = [
 		'uid', 'id', 'parent', 'uri-id', 'uri', 'thr-parent', 'parent-uri', 'guid', 'network', 'gravity',
@@ -1889,24 +1891,28 @@ class Item
 			}
 		}
 
-		DBA::lock('item');
+		if (DI::lock()->acquire(self::LOCK_INSERT, 0)) {
+			$condition = ['uri-id' => $item['uri-id'], 'uid' => $item['uid'], 'network' => $item['network']];
+			if (DBA::exists('item', $condition)) {
+				DI::lock()->release(self::LOCK_INSERT);
+				Logger::notice('Item is already inserted - aborting', $condition);
+				return 0;
+			}
 
-		$condition = ['uri-id' => $item['uri-id'], 'uid' => $item['uid'], 'network' => $item['network']];
-		if (DBA::exists('item', $condition)) {
-			DBA::unlock();
-			Logger::notice('Item is already inserted - aborting', $condition);
-			return 0;
+			$result = DBA::insert('item', $item);
+
+			// When the item was successfully stored we fetch the ID of the item.
+			$current_post = DBA::lastInsertId();
+			DI::lock()->release(self::LOCK_INSERT);
+		} else {
+			Logger::warning('Item lock had not been acquired');
+			$result = false;
+			$current_post = 0;
 		}
 
-		$ret = DBA::insert('item', $item);
-
-		// When the item was successfully stored we fetch the ID of the item.
-		$current_post = DBA::lastInsertId();
-		DBA::unlock();
-
-		if (!DBA::isResult($ret) || ($current_post == 0)) {
+		if (empty($current_post) || !DBA::isResult($result)) {
 			// On failure store the data into a spool file so that the "SpoolPost" worker can try again later.
-			Logger::warning('Could not store item. it will be spooled', ['ret' => $ret, 'id' => $current_post]);
+			Logger::warning('Could not store item. it will be spooled', ['result' => $result, 'id' => $current_post]);
 			self::spool($orig_item);
 			return 0;
 		}