From eb0c50f672654a0d09262df013c655d0494415d0 Mon Sep 17 00:00:00 2001
From: zivillian <zivillian@users.noreply.github.com>
Date: Fri, 31 May 2024 17:18:55 +0200
Subject: [PATCH] extend connection check

---
 Graphite/CarbonConnectionPool.cs | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/Graphite/CarbonConnectionPool.cs b/Graphite/CarbonConnectionPool.cs
index c0de838..af28660 100644
--- a/Graphite/CarbonConnectionPool.cs
+++ b/Graphite/CarbonConnectionPool.cs
@@ -136,6 +136,12 @@ private async Task<bool> TestAsync(TcpClient client, CancellationToken cancellat
             try
             {
                 await _formatter.TestConnectionAsync(client.GetStream(), cancellationToken).ConfigureAwait(false);
+                //https://stackoverflow.com/a/2661876/19671
+                var socket = client.Client;
+                if (!socket.Connected) return false;
+                var poll = socket.Poll(1000, SelectMode.SelectRead);
+                var empty = socket.Available == 0;
+                if (poll && empty) return false;
                 return true;
             }
             catch (IOException ex) when (ex.InnerException is SocketException se && CheckSocketException(se))
@@ -181,4 +187,4 @@ public bool Return(TcpClient obj)
             }
         }
     }
-}
\ No newline at end of file
+}