Bump uptwisted thread pool size

Change-Id: Id3b086e1b65c697cb1813f86034b6002d7a66dc4
diff --git a/voltha/main.py b/voltha/main.py
index 243bffa..bc640b6 100755
--- a/voltha/main.py
+++ b/voltha/main.py
@@ -511,7 +511,7 @@
             lambda: self.log.info('twisted-reactor-started'))
         reactor.addSystemEventTrigger('before', 'shutdown',
                                       self.shutdown_components)
-        reactor.suggestThreadPoolSize(30)
+        reactor.suggestThreadPoolSize(300)
         reactor.run()
 
     def start_heartbeat(self):