From 35d79f54e5bd99ee1b39b1659b9abca266c9d7c4 Mon Sep 17 00:00:00 2001
From: jackpoz <giacomopoz@gmail.com>
Date: Sat, 10 Feb 2018 16:07:56 +0100
Subject: [PATCH] Shared/Database: Improve dead-lock error handling

Improve dead-lock error handling in async transactions by retrying the transaction for up to 60 seconds instead of just 5 times

(cherry picked from commit 54b0b8f5ead41f936b12e97d1b4fbacd9b89ab53)

# Conflicts:
#	src/server/database/Database/Transaction.cpp
---
 src/server/database/Database/Transaction.cpp | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/server/database/Database/Transaction.cpp b/src/server/database/Database/Transaction.cpp
index afa107f31c7..7636334d5cb 100644
--- a/src/server/database/Database/Transaction.cpp
+++ b/src/server/database/Database/Transaction.cpp
@@ -22,6 +22,7 @@
 #include "Timer.h"
 #include <mysqld_error.h>
 #include <sstream>
+#include <thread>
 
 std::mutex TransactionTask::_deadlockLock;
 
@@ -121,17 +122,24 @@ bool TransactionWithResultTask::Execute()
 
     if (errorCode == ER_LOCK_DEADLOCK)
     {
+        std::ostringstream threadIdStream;
+        threadIdStream << std::this_thread::get_id();
+        std::string threadId = threadIdStream.str();
+
         // Make sure only 1 async thread retries a transaction so they don't keep dead-locking each other
         std::lock_guard<std::mutex> lock(_deadlockLock);
-        uint8 loopBreaker = 5;  // Handle MySQL Errno 1213 without extending deadlock to the core itself
-        for (uint8 i = 0; i < loopBreaker; ++i)
+        for (uint32 loopDuration = 0, startMSTime = getMSTime(); loopDuration <= DEADLOCK_MAX_RETRY_TIME_MS; loopDuration = GetMSTimeDiffToNow(startMSTime))
         {
             if (!TryExecute())
             {
                 m_result.set_value(true);
                 return true;
             }
+
+            TC_LOG_WARN("sql.sql", "Deadlocked SQL Transaction, retrying. Loop timer: %u ms, Thread Id: %s", loopDuration, threadId.c_str());
         }
+
+        TC_LOG_ERROR("sql.sql", "Fatal deadlocked SQL Transaction, it will not be retried anymore. Thread Id: %s", threadId.c_str());
     }
 
     // Clean up now.