From 60e65d8d8d0ca290f7c1cc43ea3bb3f3756d7b45 Mon Sep 17 00:00:00 2001
From: Aaron Schulz <aschulz@wikimedia.org>
Date: Thu, 29 May 2014 13:08:19 -0700
Subject: [PATCH] Made TransactionProfiler handle interlaced transactions
 better

* Previously the list of involved DBs might be incomplete

Change-Id: I75b91d3b9a951169038b40b9cf2f59707ba0c11d
---
 includes/profiler/Profiler.php | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/includes/profiler/Profiler.php b/includes/profiler/Profiler.php
index f6bafd5d7d..677f473c0d 100644
--- a/includes/profiler/Profiler.php
+++ b/includes/profiler/Profiler.php
@@ -358,7 +358,7 @@ abstract class Profiler {
 class TransactionProfiler {
 	/** @var float seconds */
 	protected $mDBLockThreshold = 5.0;
-	/** @var array DB/server name => (active trx count,timestamp) */
+	/** @var array DB/server name => (active trx count, time, DBs involved) */
 	protected $mDBTrxHoldingLocks = array();
 	/** @var array DB/server name => list of (function name, elapsed time) */
 	protected $mDBTrxMethodTimes = array();
@@ -377,9 +377,13 @@ class TransactionProfiler {
 		if ( isset( $this->mDBTrxHoldingLocks[$name] ) ) {
 			++$this->mDBTrxHoldingLocks[$name]['refs'];
 		} else {
-			$this->mDBTrxHoldingLocks[$name] = array( 'refs' => 1, 'start' => microtime( true ) );
+			$this->mDBTrxHoldingLocks[$name] = array(
+				'refs' => 1, 'start' => microtime( true ), 'conns' => array() );
 			$this->mDBTrxMethodTimes[$name] = array();
 		}
+		foreach ( $this->mDBTrxHoldingLocks as $name => &$info ) {
+			$info['conns'][$name] = 1; // track all DBs in transactions for this transaction
+		}
 	}
 
 	/**
@@ -424,15 +428,15 @@ class TransactionProfiler {
 		if ( --$this->mDBTrxHoldingLocks[$name]['refs'] <= 0 ) {
 			$slow = false;
 			foreach ( $this->mDBTrxMethodTimes[$name] as $info ) {
-				list( $method, $realtime ) = $info;
+				$realtime = $info[1];
 				if ( $realtime >= $this->mDBLockThreshold ) {
 					$slow = true;
 					break;
 				}
 			}
 			if ( $slow ) {
-				$dbs = implode( ', ', array_keys( $this->mDBTrxHoldingLocks ) );
-				$msg = "Sub-optimal transaction on DB(s) {$dbs}:\n";
+				$dbs = implode( ', ', array_keys( $this->mDBTrxHoldingLocks[$name]['conns'] ) );
+				$msg = "Sub-optimal transaction on DB(s) [{$dbs}]:\n";
 				foreach ( $this->mDBTrxMethodTimes[$name] as $i => $info ) {
 					list( $method, $realtime ) = $info;
 					$msg .= sprintf( "%d\t%.6f\t%s\n", $i, $realtime, $method );
-- 
2.20.1