[JENKINS-22938] SSH slave connections die after the slave outputs 4MB…

… of stderr, usually during findbugs analysis The fix for [JENKINS-18836], [JENKINS-18879], [JENKINS-19619] was incorrect in its analysis. - There is no call to getChannelData() on the new code path, so thus you cannot have two calls of freeupWindow() - The problem with the original call to freeupWindow() is that it is on the receiver thread. You should not mix the responsibilities. Blocking the receiver thread to send a message will negatively impact performance and connection stability. - The correct solution is to push the freeupWindow onto the async queue thus the ACK gets sent and the purity of the receiving thread can be maintained.
jenkinsci · May 14, 2014 · 5811ddd · 5811ddd
1 parent f0712eb
commit 5811ddd
Showing 1 changed file with 16 additions and 2 deletions.
diff --git a/src/com/trilead/ssh2/channel/Channel.java b/src/com/trilead/ssh2/channel/Channel.java
@@ -96,6 +96,7 @@ public void write(byte[] buf, int start, int len) throws IOException {
                 }
             } else {
                 sink.write(buf,start,len);
+                freeupWindow(len, true);
             }
         }
 
@@ -327,6 +328,14 @@ public void setReasonClosed(String reasonClosed)
      * let it send more data.
      */
     void freeupWindow(int copylen) throws IOException {
+        freeupWindow(copylen, false);
+	}
+
+    /**
+     * Update the flow control couner and if necessary, sends ACK to the other end to
+     * let it send more data.
+     */
+    void freeupWindow(int copylen, boolean sendAsync) throws IOException {
         if (copylen <= 0) return;
 
         int increment = 0;
@@ -375,8 +384,13 @@ void freeupWindow(int copylen) throws IOException {
                 msg[7] = (byte) (increment >> 8);
                 msg[8] = (byte) (increment);
 
-                if (closeMessageSent == false)
-                    cm.tm.sendMessage(msg);
+                if (closeMessageSent == false) {
+                    if (sendAsync) {
+                        cm.tm.sendAsynchronousMessage(msg);
+                    } else {
+                        cm.tm.sendMessage(msg);
+                    }
+                }
             }
         }
     }