diff --git a/src/HttpHandler/Guzzle6HttpHandler.php b/src/HttpHandler/Guzzle6HttpHandler.php
index 95926d3a5..f8fbcf7dd 100644
--- a/src/HttpHandler/Guzzle6HttpHandler.php
+++ b/src/HttpHandler/Guzzle6HttpHandler.php
@@ -67,7 +67,7 @@ public function __invoke(RequestInterface $request, array $options = [])
             $requestEvent->payload = $request->getBody()->getContents();
             $requestEvent->retryAttempt = $options['retryAttempt'] ?? null;
             $requestEvent->serviceName = $options['serviceName'] ?? null;
-            $requestEvent->processId = getmypid();
+            $requestEvent->processId = (int) getmypid();
             $requestEvent->requestId = $options['requestId'] ?? crc32((string) spl_object_id($request) . getmypid());
 
             $this->logRequest($requestEvent);
@@ -111,7 +111,7 @@ public function async(RequestInterface $request, array $options = [])
             $requestEvent->payload = $request->getBody()->getContents();
             $requestEvent->retryAttempt = $options['retryAttempt'] ?? null;
             $requestEvent->serviceName = $options['serviceName'] ?? null;
-            $requestEvent->processId = getmypid();
+            $requestEvent->processId = (int) getmypid();
             $requestEvent->requestId = $options['requestId'] ?? crc32((string) spl_object_id($request) . getmypid());
 
             $this->logRequest($requestEvent);