From ffef9d9fe8fdf7ff176b57d975f7610518d47ca8 Mon Sep 17 00:00:00 2001
From: Marc Blank <mblank@google.com>
Date: Sun, 4 Oct 2009 20:57:03 -0700
Subject: [PATCH] Help with another push inconsistency edge case (#2131432)

* If we are forced to abort a "ping" due to a watchdog alarm, we should
  handle this as a ping failure (which potentially changes the heartbeat)
  rather than a garden variety IOException.
* This prevents the additional overhead of connection error backoffs,
  which would only tend to increase the time needed to recover from the
  error.
* In one case reported by Moto, this appears to be the behavior of a WiFi
  router with NAT timeout.  This fix will cause maximum delay for pushed
  mail to be reduced in most cases.

Change-Id: I2b0e3b10d82762d20f63cac3ac4638a03f13f842
---
 src/com/android/exchange/EasSyncService.java | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/com/android/exchange/EasSyncService.java b/src/com/android/exchange/EasSyncService.java
index 540f1a2a0..b2532a1c5 100644
--- a/src/com/android/exchange/EasSyncService.java
+++ b/src/com/android/exchange/EasSyncService.java
@@ -141,6 +141,8 @@ public class EasSyncService extends AbstractSyncService {
     private int mPingHighWaterMark = 0;
     // Whether we've ever lowered the heartbeat
     private boolean mPingHeartbeatDropped = false;
+    // Whether a POST was aborted due to watchdog timeout
+    private boolean mAborted = false;
 
     public EasSyncService(Context _context, Mailbox _mailbox) {
         super(_context, _mailbox);
@@ -164,6 +166,7 @@ public class EasSyncService extends AbstractSyncService {
         synchronized(getSynchronizer()) {
             if (mPendingPost != null) {
                 userLog("Aborting pending POST!");
+                mAborted = true;
                 mPendingPost.abort();
             }
         }
@@ -769,7 +772,8 @@ public class EasSyncService extends AbstractSyncService {
                     // haven't yet "fixed" the timeout, back off by two minutes and "fix" it
                     boolean hasMessage = message != null;
                     userLog("IOException runPingLoop: " + (hasMessage ? message : "[no message]"));
-                    if (hasMessage && message.contains("reset by peer")) {
+                    if (mAborted || (hasMessage && message.contains("reset by peer"))) {
+                        long pingLength = SystemClock.elapsedRealtime() - pingTime;
                         if ((pingHeartbeat > PING_MIN_HEARTBEAT) &&
                                 (pingHeartbeat > mPingHighWaterMark)) {
                             pingHeartbeat -= PING_HEARTBEAT_INCREMENT;
@@ -778,8 +782,8 @@ public class EasSyncService extends AbstractSyncService {
                                 pingHeartbeat = PING_MIN_HEARTBEAT;
                             }
                             userLog("Decreased ping heartbeat to ", pingHeartbeat, "s");
-                        } else if ((SystemClock.elapsedRealtime() - pingTime) < 2000) {
-                            userLog("NAT type IOException < 2 seconds; throwing IOException");
+                        } else if (mAborted || (pingLength < 2000)) {
+                            userLog("Abort or NAT type return < 2 seconds; throwing IOException");
                             throw e;
                         } else {
                             userLog("NAT type IOException > 2 seconds?");