bug #109 perf: ensure timely flush stream buffers (cidosx)

This PR was merged into the 2.1-dev branch.

Discussion
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perf: ensure timely flush stream buffers

Resolve OOM problem while handle a large streamed response

Commits
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8c8a75b perf: ensure timely flush stream buffers

Author: derrabus

Factory/PsrHttpFactory.php

@@ -142,7 +142,7 @@ public function createResponse(Response $symfonyResponse)
                     $stream->write($buffer);
 
                     return '';
-                });
+                }, 1);
 
                 $symfonyResponse->sendContent();
                 ob_end_clean();