diff --git a/lib/nghttp2_frame.h b/lib/nghttp2_frame.h
index 5f6152b7..ecc1e3ba 100644
--- a/lib/nghttp2_frame.h
+++ b/lib/nghttp2_frame.h
@@ -53,7 +53,7 @@
   (NGHTTP2_FRAME_HDLEN + 1 + NGHTTP2_MAX_PAYLOADLEN)
 
 /* The default length of DATA frame payload. */
-#define NGHTTP2_DATA_PAYLOADLEN NGHTTP2_MAX_FRAME_SIZE_MIN
+#define NGHTTP2_DATA_PAYLOADLEN 256*1024
 
 /* Maximum headers block size to send, calculated using
    nghttp2_hd_deflate_bound().  This is the default value, and can be
diff --git a/lib/nghttp2_session.c b/lib/nghttp2_session.c
index 93f3f07c..5a4222fa 100644
--- a/lib/nghttp2_session.c
+++ b/lib/nghttp2_session.c
@@ -7748,6 +7748,21 @@ int nghttp2_session_pack_data(nghttp2_session *session, nghttp2_bufs *bufs,
     datamax = (size_t)payloadlen;
   }
 
+  if ((size_t)datamax > nghttp2_buf_avail(buf)) {
+      /* Resize the current buffer(s).  The reason why we do +1 for
+         buffer size is for possible padding field. */
+      rv = nghttp2_bufs_realloc(&session->aob.framebufs,
+                                (size_t)(NGHTTP2_FRAME_HDLEN + 1 + datamax));
+
+      if (rv != 0) {
+        DEBUGF("send: realloc buffer failed rv=%d", rv);
+      } else {
+        assert(&session->aob.framebufs == bufs);
+
+        buf = &bufs->cur->buf;
+      }
+    }
+
   /* Current max DATA length is less then buffer chunk size */
   assert(nghttp2_buf_avail(buf) >= datamax);
 
diff --git a/src/HttpServer.h b/src/HttpServer.h
index cde34798..69155808 100644
--- a/src/HttpServer.h
+++ b/src/HttpServer.h
@@ -205,7 +205,7 @@ public:
 
   struct ev_loop *get_loop() const;
 
-  using WriteBuf = Buffer<64_k>;
+  using WriteBuf = Buffer<512_k>; // This needs to be >= largest frame sent, or frame is not sent
 
   WriteBuf *get_wb();