From b0e159fc552334bbdb075596aa115cd875aaf6bf Mon Sep 17 00:00:00 2001
From: Christopher Kohlhoff <chris@kohlhoff.com>
Date: Fri, 17 Nov 2006 11:40:48 +0000
Subject: [PATCH] Add a workaround for an apparent Windows bug where the
 delivery of asynchronous I/O completions is delayed if the thread used to
 start the operation is CPU bound.

[SVN r36069]
---
 include/boost/asio/detail/win_iocp_io_service.hpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/include/boost/asio/detail/win_iocp_io_service.hpp b/include/boost/asio/detail/win_iocp_io_service.hpp
index 25458775..1d971d54 100644
--- a/include/boost/asio/detail/win_iocp_io_service.hpp
+++ b/include/boost/asio/detail/win_iocp_io_service.hpp
@@ -260,11 +260,15 @@ private:
       LPOVERLAPPED overlapped = 0;
       ::SetLastError(0);
       BOOL ok = ::GetQueuedCompletionStatus(iocp_.handle, &bytes_transferred,
-          &completion_key, &overlapped, block ? INFINITE : 0);
+          &completion_key, &overlapped, block ? 1000 : 0);
       DWORD last_error = ::GetLastError();
 
       if (!ok && overlapped == 0)
+      {
+        if (block && last_error == WAIT_TIMEOUT)
+          continue;
         return 0;
+      }
 
       if (overlapped)
       {