* Spawn a maximum of x-WORKER_THREADS threads per db-command. Prevents mass-resolving from blocking all other commands.

src/libtomahawk/database/database.cpp

@@ -19,14 +19,6 @@ Database::Database( const QString& dbname, QObject* parent )
 {
     s_instance = this;
 
-    for ( int i = 0; i < WORKER_THREADS; i++ )
-    {
-        DatabaseWorker* worker = new DatabaseWorker( m_impl, this, false );
-        worker->start();
-
-        m_workersRO << worker;
-    }
-
     m_workerRW->start();
 }
 
@@ -35,7 +27,7 @@ Database::~Database()
 {
     qDebug() << Q_FUNC_INFO;
 
-    qDeleteAll( m_workersRO );
+    qDeleteAll( m_workers );
     delete m_workerRW;
     delete m_impl;
 }
@@ -58,13 +50,23 @@ Database::enqueue( QSharedPointer<DatabaseCommand> lc )
     }
     else
     {
-//        qDebug() << Q_FUNC_INFO << "RO" << lc->commandname();
+        // find existing amount of worker threads for commandname
+        // create new thread if < WORKER_THREADS
+        if ( m_workers.count( lc->commandname() ) < WORKER_THREADS )
+        {
+            DatabaseWorker* worker = new DatabaseWorker( m_impl, this, false );
+            worker->start();
 
+            m_workers.insertMulti( lc->commandname(), worker );
+        }
+
+        // find thread for commandname with lowest amount of outstanding jobs and enqueue job
         int busyThreads = 0;
         DatabaseWorker* happyThread = 0;
-        for ( int i = 0; i < m_workersRO.count(); i++ )
+        QList< DatabaseWorker* > workers = m_workers.values( lc->commandname() );
+        for ( int i = 0; i < workers.count(); i++ )
         {
-            DatabaseWorker* worker = m_workersRO.at( i );
+            DatabaseWorker* worker = workers.at( i );
 
             if ( !worker->busy() )
             {
@@ -83,7 +85,7 @@ Database::enqueue( QSharedPointer<DatabaseCommand> lc )
 }
 
 
-const QString&
+QString
 Database::dbid() const
 {
     return m_impl->dbid();

src/libtomahawk/database/database.h

@@ -29,7 +29,7 @@ public:
     explicit Database( const QString& dbname, QObject* parent = 0 );
     ~Database();
 
-    const QString& dbid() const;
+    QString dbid() const;
     const bool indexReady() const { return m_indexReady; }
 
     void loadIndex();
@@ -45,7 +45,7 @@ public slots:
 private:
     DatabaseImpl* m_impl;
     DatabaseWorker* m_workerRW;
-    QList<DatabaseWorker*> m_workersRO;
+    QHash< QString, DatabaseWorker* > m_workers;
     bool m_indexReady;
 
     static Database* s_instance;

src/libtomahawk/database/databaseimpl.h

@@ -55,7 +55,7 @@ public:
     // indexes entries from "table" where id >= pkey
     void updateSearchIndex();
 
-    const QString& dbid() const { return m_dbid; }
+    QString dbid() const { return m_dbid; }
 
     void loadIndex();
 

src/libtomahawk/pipeline.cpp

@@ -2,6 +2,7 @@
 
 #include <QDebug>
 #include <QMutexLocker>
+#include <QTimer>
 
 #include "functimeout.h"
 #include "database/database.h"
@@ -180,8 +181,9 @@ Pipeline::shuntNext()
         q = m_queries_pending.takeFirst();
         q->setLastPipelineWeight( 101 );
     }
-    
-    shunt( q ); // bump into next stage of pipeline (highest weights are 100)
+
+    if ( !q.isNull() )
+        shunt( q ); // bump into next stage of pipeline (highest weights are 100)
 }
 
 
@@ -192,8 +194,11 @@ Pipeline::shunt( const query_ptr& q )
     {
         qDebug() << "Query solved, pipeline aborted:" << q->toString()
                  << "numresults:" << q->results().length();
+
+        shuntNext();
         return;
     }
+
     unsigned int lastweight = 0;
     unsigned int lasttimeout = 0;
     foreach( Resolver* r, m_resolvers )