From 46fc9cb20a73c85827c77d578b2605fd88e71feb Mon Sep 17 00:00:00 2001
From: Christian Muehlhaeuser <muesli@gmail.com>
Date: Wed, 15 Jun 2011 04:15:27 +0200
Subject: [PATCH] * Be cleverer with database threads, too.

---
 src/libtomahawk/database/database.cpp | 10 +++++++---
 src/libtomahawk/database/database.h   |  7 ++++---
 2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/src/libtomahawk/database/database.cpp b/src/libtomahawk/database/database.cpp
index 4436f6cfa..bd6b81e49 100644
--- a/src/libtomahawk/database/database.cpp
+++ b/src/libtomahawk/database/database.cpp
@@ -1,5 +1,5 @@
 /* === This file is part of Tomahawk Player - <http://tomahawk-player.org> ===
- * 
+ *
  *   Copyright 2010-2011, Christian Muehlhaeuser <muesli@tomahawk-player.org>
  *
  *   Tomahawk is free software: you can redistribute it and/or modify
@@ -18,7 +18,8 @@
 
 #include "database.h"
 
-#define WORKER_THREADS 5
+#define DEFAULT_WORKER_THREADS 4
+#define MAX_WORKER_THREADS 16
 
 Database* Database::s_instance = 0;
 
@@ -38,6 +39,9 @@ Database::Database( const QString& dbname, QObject* parent )
 {
     s_instance = this;
 
+    m_maxConcurrentThreads = qBound( DEFAULT_WORKER_THREADS, QThread::idealThreadCount() * 2, MAX_WORKER_THREADS );
+    qDebug() << Q_FUNC_INFO << "Using" << m_maxConcurrentThreads << "threads";
+
     connect( m_impl, SIGNAL( indexReady() ), SIGNAL( indexReady() ) );
     connect( m_impl, SIGNAL( indexReady() ), SIGNAL( ready() ) );
     connect( m_impl, SIGNAL( indexReady() ), SLOT( setIsReadyTrue() ) );
@@ -76,7 +80,7 @@ Database::enqueue( QSharedPointer<DatabaseCommand> lc )
     {
         // find existing amount of worker threads for commandname
         // create new thread if < WORKER_THREADS
-        if ( m_workers.count( lc->commandname() ) < WORKER_THREADS )
+        if ( m_workers.count( lc->commandname() ) < m_maxConcurrentThreads )
         {
             DatabaseWorker* worker = new DatabaseWorker( m_impl, this, false );
             worker->start();
diff --git a/src/libtomahawk/database/database.h b/src/libtomahawk/database/database.h
index df02ce2a0..678cca01b 100644
--- a/src/libtomahawk/database/database.h
+++ b/src/libtomahawk/database/database.h
@@ -1,5 +1,5 @@
 /* === This file is part of Tomahawk Player - <http://tomahawk-player.org> ===
- * 
+ *
  *   Copyright 2010-2011, Christian Muehlhaeuser <muesli@tomahawk-player.org>
  *
  *   Tomahawk is free software: you can redistribute it and/or modify
@@ -52,7 +52,7 @@ public:
     bool indexReady() const { return m_indexReady; }
 
     void loadIndex();
-    
+
     bool isReady() const { return m_ready; }
 
 signals:
@@ -67,13 +67,14 @@ public slots:
 
 private slots:
     void setIsReadyTrue() { m_ready = true; }
-    
+
 private:
     bool m_ready;
     DatabaseImpl* m_impl;
     DatabaseWorker* m_workerRW;
     QHash< QString, DatabaseWorker* > m_workers;
     bool m_indexReady;
+    int m_maxConcurrentThreads;
 
     static Database* s_instance;
 };