From 4cd7d3f8966102742d75cc60a9e93308b44026cf Mon Sep 17 00:00:00 2001
From: lythesia <iranaikimi@gmail.com>
Date: Thu, 19 Feb 2015 21:51:44 +0800
Subject: [PATCH] retry backend connection

---
 pkg/R/sparkR.R | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/pkg/R/sparkR.R b/pkg/R/sparkR.R
index 2218170fef104..7d42842dc8847 100644
--- a/pkg/R/sparkR.R
+++ b/pkg/R/sparkR.R
@@ -110,9 +110,19 @@ sparkR.init <- function(
                 mainClass = "edu.berkeley.cs.amplab.sparkr.SparkRBackend",
                 args = as.character(sparkRBackendPort),
                 javaOpts = paste("-Xmx", sparkMem, sep = ""))
-  Sys.sleep(2) # Wait for backend to come up
+
+  cat("Waiting JVM bring up ...\n")
+  while(TRUE) {
+    if(!connExists(.sparkREnv)) {
+      Sys.sleep(1)
+      cat(".")
+      connectBackend("localhost", sparkRBackendPort) # Connect to it
+    } else {
+      cat(" ok.\n")
+      break
+    }
+  }
   .sparkREnv$sparkRBackendPort <- sparkRBackendPort
-  connectBackend("localhost", sparkRBackendPort) # Connect to it
 
   if (nchar(sparkHome) != 0) {
     sparkHome <- normalizePath(sparkHome)