Make fattn optional

src/AceStepWorker.cpp

@@ -55,6 +55,11 @@ void AceStepWorker::setLowVramMode(bool enabled)
 	m_lowVramMode = enabled;
 }
 
+void AceStepWorker::setFlashAttention(bool enabled)
+{
+	m_flashAttention = enabled;
+}
+
 bool AceStepWorker::isGenerating(SongItem* song)
 {
 	if (!m_busy.load() && song)
@@ -440,7 +445,7 @@ bool AceStepWorker::loadModels()
 	ace_lm_default_params(&lmParams);
 	lmParams.model_path = m_lmModelPathBytes.constData();
 	lmParams.use_fsm = true;
-	lmParams.use_fa = true;
+	lmParams.use_fa = m_flashAttention;
 
 	m_lmContext = ace_lm_load(&lmParams);
 	if (!m_lmContext)
@@ -455,7 +460,7 @@ bool AceStepWorker::loadModels()
 	synthParams.text_encoder_path = m_textEncoderPathBytes.constData();
 	synthParams.dit_path = m_ditPathBytes.constData();
 	synthParams.vae_path = m_vaePathBytes.constData();
-	synthParams.use_fa = true;
+	synthParams.use_fa = m_flashAttention;
 
 	m_synthContext = ace_synth_load(&synthParams);
 	if (!m_synthContext)
@@ -494,7 +499,7 @@ bool AceStepWorker::loadLm()
 	ace_lm_default_params(&lmParams);
 	lmParams.model_path = m_lmModelPathBytes.constData();
 	lmParams.use_fsm = true;
-	lmParams.use_fa = true;
+	lmParams.use_fa = m_flashAttention;
 
 	m_lmContext = ace_lm_load(&lmParams);
 	if (!m_lmContext)
@@ -524,7 +529,7 @@ bool AceStepWorker::loadSynth()
 	synthParams.text_encoder_path = m_textEncoderPathBytes.constData();
 	synthParams.dit_path = m_ditPathBytes.constData();
 	synthParams.vae_path = m_vaePathBytes.constData();
-	synthParams.use_fa = true;
+	synthParams.use_fa = m_flashAttention;
 
 	m_synthContext = ace_synth_load(&synthParams);
 	if (!m_synthContext)

src/AceStepWorker.h

@@ -38,6 +38,10 @@ public:
 	void setLowVramMode(bool enabled);
 	bool isLowVramMode() const { return m_lowVramMode; }
 
+	// Flash attention mode
+	void setFlashAttention(bool enabled);
+	bool isFlashAttention() const { return m_flashAttention; }
+
 	// Request a new song generation
 	bool requestGeneration(SongItem song, QString requestTemplate);
 
@@ -75,6 +79,7 @@ private:
 	std::atomic<bool> m_cancelRequested{false};
 	std::atomic<bool> m_modelsLoaded{false};
 	bool m_lowVramMode = false;
+	bool m_flashAttention = true;
 
 	// Current request data
 	SongItem m_currentSong;

src/AdvancedSettingsDialog.cpp

@@ -55,6 +55,11 @@ bool AdvancedSettingsDialog::getLowVramMode() const
 	return ui->lowVramCheckBox->isChecked();
 }
 
+bool AdvancedSettingsDialog::getFlashAttention() const
+{
+	return ui->flashAttentionCheckBox->isChecked();
+}
+
 void AdvancedSettingsDialog::setJsonTemplate(const QString &templateStr)
 {
 	ui->jsonTemplateEdit->setPlainText(templateStr);
@@ -90,6 +95,11 @@ void AdvancedSettingsDialog::setLowVramMode(bool enabled)
 	ui->lowVramCheckBox->setChecked(enabled);
 }
 
+void AdvancedSettingsDialog::setFlashAttention(bool enabled)
+{
+	ui->flashAttentionCheckBox->setChecked(enabled);
+}
+
 void AdvancedSettingsDialog::on_aceStepBrowseButton_clicked()
 {
 	QString dir = QFileDialog::getExistingDirectory(this, "Select AceStep Build Directory", ui->aceStepPathEdit->text());

src/AdvancedSettingsDialog.h

@@ -30,6 +30,7 @@ public:
 	QString getDiTModelPath() const;
 	QString getVAEModelPath() const;
 	bool getLowVramMode() const;
+	bool getFlashAttention() const;
 
 	// Setters for settings
 	void setJsonTemplate(const QString &templateStr);
@@ -39,6 +40,7 @@ public:
 	void setDiTModelPath(const QString &path);
 	void setVAEModelPath(const QString &path);
 	void setLowVramMode(bool enabled);
+	void setFlashAttention(bool enabled);
 
 private slots:
 	void on_aceStepBrowseButton_clicked();

src/AdvancedSettingsDialog.ui

@@ -42,6 +42,26 @@
 								                                                                         </widget>
 								                                                                         </item>
 								<item>
+							<widget class="QCheckBox" name="flashAttentionCheckBox">
+								                                                                         <property name="text">
+								                                                                             <string>Flash Attention</string>
+								                                                                         </property>
+								                                                                         <property name="checked">
+								                                                                                 <bool>true</bool>
+								                                                                         </property>
+								                                                                         </widget>
+								                                                                         </item>
+								<item>
+							<widget class="QLabel" name="flashAttentionLabel">
+								                                                                         <property name="text">
+								                                                                             <string>Use flash attention for faster generation. Disable if experiencing issues.</string>
+								                                                                         </property>
+								                                                                         <property name="wordWrap">
+								                                                                                 <bool>true</bool>
+								                                                                         </property>
+								                                                                         </widget>
+								                                                                         </item>
+								<item>
 							<spacer name="verticalSpacer">
 							                                 <property name="orientation">
 							                                     <enum>Qt::Vertical</enum>

src/MainWindow.cpp

@@ -159,6 +159,10 @@ void MainWindow::loadSettings()
 	// Load low VRAM mode
 	bool lowVram = settings.value("lowVramMode", false).toBool();
 	aceStep->setLowVramMode(lowVram);
+
+	// Load flash attention setting
+	bool flashAttention = settings.value("flashAttention", true).toBool();
+	aceStep->setFlashAttention(flashAttention);
 }
 
 void MainWindow::saveSettings()
@@ -181,6 +185,9 @@ void MainWindow::saveSettings()
 	// Save low VRAM mode
 	settings.setValue("lowVramMode", aceStep->isLowVramMode());
 
+	// Save flash attention setting
+	settings.setValue("flashAttention", aceStep->isFlashAttention());
+
 	settings.setValue("firstRun", false);
 }
 
@@ -382,6 +389,7 @@ void MainWindow::on_advancedSettingsButton_clicked()
 	dialog.setDiTModelPath(ditModelPath);
 	dialog.setVAEModelPath(vaeModelPath);
 	dialog.setLowVramMode(aceStep->isLowVramMode());
+	dialog.setFlashAttention(aceStep->isFlashAttention());
 
 	if (dialog.exec() == QDialog::Accepted)
 	{
@@ -408,6 +416,9 @@ void MainWindow::on_advancedSettingsButton_clicked()
 		// Update low VRAM mode
 		aceStep->setLowVramMode(dialog.getLowVramMode());
 
+		// Update flash attention setting
+		aceStep->setFlashAttention(dialog.getFlashAttention());
+
 		saveSettings();
 	}
 }