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Delay to open window after use my desktop app(open and close many windows), when more windows I open, larger will be the delay



  • Hello,

    When I use my app for some time, opening and closing many windows, the open time for each window is longer.
    One thing I note is, the memory used becames bigger for each window opened.
    594ef9cf-b918-4dfd-b587-4dac0e914cfe-image.png

    I think one code, capable to clear this memory could be usefull, or some other solution.

    Someone could help me please? Thank you



  • @andre_sophia
    One thing: I think you are re-connect()-ing all the time, setting up slots on signals again & again.

    E.g.

    def Menu_Cadastro_Func():
    	Menu_Cadastro.pushButton.clicked.connect(Menu_Principal_Func)
    
    def Menu_Principal_Func():
    	Menu_Principal.pushButton_3.clicked.connect(Menu_Cadastro_Func)
    

    Since you are closing (but not destroying/getting rid of) these windows all the time, the connect() will build up. ( @jsulm will correct me if I'm wrong, but I do not think Qt checks for an exact duplicate connnect() and skips it, I think it adds it again.) If that's right, then I think you start to show/hide (the same) windows multiple times the more you click around....


  • Qt Champions 2019

    @andre_sophia said in Delay to open window after use my desktop app(open and close many windows), when more windows I open, larger will be the delay:

    I think one code, capable to clear this memory could be usefull

    Well, it sounds like memory leak. Use a tool to analyse memory consumption of your app.
    With the information you provided it is impossible to tell you what exactly the problem is.
    How many windows do you open?
    What is your app doing?
    What does each window do?



  • @andre_sophia
    As @jsulm has said/asked.
    My guess: you are opening windows without the old ones being properly disposed/freed, so the memory gets worse.
    Make sure your Python code is not keeping references to closed windows. Consider using Qt::WA_DeleteOnClose flag. Use QApplication.allWidgets()/QApplication.topLevelWidgets() to look through the widgets which are still in the application to see if there are old, closed ones you would not expect to be around any longer.



  • @jsulm Thanks for your help, The app has 13 windows, but when I open one, I close the other, so always with only one window open.

    At this moment, my windows don't have functionality, only buttons connections (to to navigate between windows) as below:

    b993bc94-649f-44ee-bad6-1e7af42e4e0e-image.png

    When I navigate for 10 windows (opening and closing them, without close the app) the delay begin, and only increase.

    If you want to know something more, please reply me.
    Thank you.



  • @JonB Thanks for your help. I always close a window to open another one, but the memory does't decrease.
    Could you please send me an example of how I can use the Qt::WA_DeleteOnClose in Python?

    Thank you so much!


  • Qt Champions 2019

    @andre_sophia said in Delay to open window after use my desktop app(open and close many windows), when more windows I open, larger will be the delay:

    Could you please send me an example of how I can use the Qt::WA_DeleteOnClose in Python?

    See https://stackoverflow.com/questions/32477930/qtwa-deleteonclose - is for C++, but works same with Python. Also you can delete the window manually: assign None to the variable holding the window object or use del.



  • @jsulm
    Hi. I believe you are a native C++-er, not Pythonista. Be aware of the following nasty for Python + Qt. I will keep it brief here, no example, as I don't suppose it applies to this OP's current situation.

    In Python you cannot delete an object, assigning None does not do it, and nor does going del. Python maintains its own reference count to objects, and only deletes them when that reaches 0. Having, say, a QDialog with a connect() to a class-member method does allow the dialog to be deleted when the referencing variable goes out of scope/assign None/use del. However, if you connect() to a Python lambda for the slot --- as we all often do --- this creates a "dangling" reference to it which Python never collects and keeps the reference count > 0. Such a QDialog will never be deleted!

    Consequently, I set Qt.WA_DeleteOnClose on my Python dialogs as the only way to achieve deletion in such a case.


  • Qt Champions 2019

    @JonB said in Delay to open window after use my desktop app(open and close many windows), when more windows I open, larger will be the delay:

    Python maintains its own reference count to objects, and only deletes them when that reaches 0

    Yes, I know. But didn't think about lambdas :-)



  • @andre_sophia said in Delay to open window after use my desktop app(open and close many windows), when more windows I open, larger will be the delay:

    but when I open one, I close the other
    When I navigate for 10 windows (opening and closing them, without close the app) the delay begin, and only increase.
    If you want to know something more, please reply me.

    Just closing windows does not necessarily delete them. We would need to see your code. Just how many times do you hit a line creating a new window?

    Having said that: if you are only going through your code a few times, even if it "leaks" windows I would not expect it to get noticeably slower till you had done this a lot of times. So again, we need to know what your code is doing.



  • @JonB my main code below:

    # -*- coding: utf-8 -*- --noconsole
    
    import sys
    from PySide2.QtCore import (QCoreApplication, QDate, QDateTime, QMetaObject,
        QObject, QPoint, QRect, QSize, QTime, QUrl, Qt)
    from PySide2 import QtCore, QtGui, QtWidgets
    from Av_Audicao import Ui_Av_Audicao
    from Av_Fala import Ui_Av_Fala
    from Av_Linguagem import Ui_Av_Linguagem
    from Av_Voz import Ui_Av_Voz
    from Cadastro_Paciente import Ui_Cadastro_Paciente
    from Consulta import Ui_Consulta
    from Editar_Paciente import Ui_Editar_Paciente
    from Fatores_Desencadeantes import Ui_Fatores_Desencadeantes
    from Fatores_Relevantes import Ui_Fatores_Relevantes
    from Menu_Cadastro import Ui_Menu_Cadastro
    from Menu_Principal import Ui_Menu_Principal
    from Menu_Triagem import Ui_Menu_Triagem
    from Queixas import Ui_Queixas
    import time
    
    
    '''Declaração das telas/Classes'''
    
    class Av_Audicao(QtWidgets.QMainWindow, Ui_Av_Audicao):
        def __init__(self):
            super(Av_Audicao, self).__init__()
            self.setupUi(self)
    
    class Av_Fala(QtWidgets.QMainWindow, Ui_Av_Fala):
        def __init__(self):
            super(Av_Fala, self).__init__()
            self.setupUi(self)
    
    class Av_Linguagem(QtWidgets.QMainWindow, Ui_Av_Linguagem):
        def __init__(self):
            super(Av_Linguagem, self).__init__()
            self.setupUi(self)
    
    class Av_Voz(QtWidgets.QMainWindow, Ui_Av_Voz):
        def __init__(self):
            super(Av_Voz, self).__init__()
            self.setupUi(self)
    
    class Cadastro_Paciente(QtWidgets.QMainWindow, Ui_Cadastro_Paciente):
        def __init__(self):
            super(Cadastro_Paciente, self).__init__()
            self.setupUi(self)
    
    class Consulta(QtWidgets.QMainWindow, Ui_Consulta):
        def __init__(self):
            super(Consulta, self).__init__()
            self.setupUi(self)
    
    class Editar_Paciente(QtWidgets.QMainWindow, Ui_Editar_Paciente):
        def __init__(self):
            super(Editar_Paciente, self).__init__()
            self.setupUi(self)
    
    class Fatores_Desencadeantes(QtWidgets.QMainWindow, Ui_Fatores_Desencadeantes):
        def __init__(self):
            super(Fatores_Desencadeantes, self).__init__()
            self.setupUi(self)
    
    class Fatores_Relevantes(QtWidgets.QMainWindow, Ui_Fatores_Relevantes):
        def __init__(self):
            super(Fatores_Relevantes, self).__init__()
            self.setupUi(self)
    
    class Menu_Cadastro(QtWidgets.QMainWindow, Ui_Menu_Cadastro):
        def __init__(self):
            super(Menu_Cadastro, self).__init__()
            self.setupUi(self)
    
    class Menu_Principal(QtWidgets.QMainWindow, Ui_Menu_Principal):
        def __init__(self):
            super(Menu_Principal, self).__init__()
            self.setupUi(self)
    
    class Menu_Triagem(QtWidgets.QMainWindow, Ui_Menu_Triagem):
        def __init__(self):
            super(Menu_Triagem, self).__init__()
            self.setupUi(self)
    
    class Queixas(QtWidgets.QMainWindow, Ui_Queixas):
        def __init__(self):
            super(Queixas, self).__init__()
            self.setupUi(self)
    
    
    ''' FUNÇÕES UTILITÁRIAS'''
    
    
    
    
    
    ''' FUNÇÕES DAS TELAS'''
    
    def Fatores_Relevantes_Func():
    	Fatores_Relevantes.showMaximized()
    
    	Fatores_Relevantes.pushButton.clicked.connect(Menu_Triagem_Func)
    
    def Fatores_Desencadeantes_Func():
    	Fatores_Desencadeantes.showMaximized()
    
    	Fatores_Desencadeantes.pushButton.clicked.connect(Menu_Triagem_Func)
    
    def Queixas_Func():
    	Queixas.showMaximized()
    
    	Queixas.pushButton.clicked.connect(Menu_Triagem_Func)
    
    def Av_Voz_Func():
    	Av_Voz.showMaximized()
    
    	Av_Voz.pushButton.clicked.connect(Menu_Triagem_Func)
    
    def Av_Fala_Func():
    	Av_Fala.showMaximized()
    
    	Av_Fala.pushButton.clicked.connect(Menu_Triagem_Func)
    
    
    def Av_Linguagem_Func():
    	Av_Linguagem.showMaximized()
    
    	Av_Linguagem.pushButton.clicked.connect(Menu_Triagem_Func)
    
    
    def Av_Audicao_Func():
    	Av_Audicao.showMaximized()
    
    	Av_Audicao.pushButton.clicked.connect(Menu_Triagem_Func)
    
    def Menu_Triagem_Func():
    	Menu_Triagem.showMaximized()
    	Menu_Principal.close()
    	Fatores_Relevantes.close()
    	Fatores_Desencadeantes.close()
    	Queixas.close()
    	Av_Voz.close()
    	Av_Fala.close()
    	Av_Linguagem.close()
    	Av_Audicao.close()
    
    
    	Menu_Triagem.pushButton.clicked.connect(Menu_Principal_Func)
    
    	Menu_Triagem.pushButton_10.clicked.connect(Fatores_Relevantes_Func)
    	Menu_Triagem.pushButton_12.clicked.connect(Fatores_Desencadeantes_Func)
    	Menu_Triagem.pushButton_11.clicked.connect(Queixas_Func)
    	Menu_Triagem.pushButton_6.clicked.connect(Av_Voz_Func)
    	Menu_Triagem.pushButton_7.clicked.connect(Av_Fala_Func)
    	Menu_Triagem.pushButton_8.clicked.connect(Av_Linguagem_Func)
    	Menu_Triagem.pushButton_9.clicked.connect(Av_Audicao_Func)
    
    
    
    
    
    def Consulta_Func():
    	Consulta.showMaximized()
    	Menu_Principal.close()
    
    	Consulta.pushButton_4.clicked.connect(Menu_Principal_Func)
    
    def Criar_Paciente_Func():
    	Cadastro_Paciente.showMaximized()
    	Menu_Cadastro.close()
    
    	Cadastro_Paciente.pushButton_4.clicked.connect(Menu_Cadastro_Func)
    
    
    def Editar_Paciente_Func():# Buscar pacientes e abrir formulário de cadastro com campos já preenchidos
    	Menu_Cadastro.close()
    	Editar_Paciente.showMaximized()	
    
    	Editar_Paciente.pushButton_4.clicked.connect(Menu_Cadastro_Func)
    
    def Menu_Cadastro_Func():
    	Editar_Paciente.close()
    	Cadastro_Paciente.close()
    	Menu_Cadastro.showMaximized()
    	Menu_Principal.close()
    
    	Menu_Cadastro.pushButton.clicked.connect(Menu_Principal_Func)
    	Menu_Cadastro.pushButton_2.clicked.connect(Editar_Paciente_Func)
    	Menu_Cadastro.pushButton_3.clicked.connect(Criar_Paciente_Func)
    
    
    def Menu_Principal_Func():
    	Menu_Cadastro.close()
    	Menu_Triagem.close()
    	Consulta.close()
    
    	Menu_Principal.showMaximized()
    
    	Menu_Principal.pushButton_3.clicked.connect(Menu_Cadastro_Func)
    	Menu_Principal.pushButton.clicked.connect(Menu_Triagem_Func)
    	Menu_Principal.pushButton_2.clicked.connect(Consulta_Func)
    
    
    
    
    
    
    
    
    if __name__ == "__main__":
        app = QtWidgets.QApplication(sys.argv)
    
        '''instância das classes'''
    
        Av_Audicao = Av_Audicao()
        Av_Fala = Av_Fala()
        Av_Linguagem = Av_Linguagem()
        Av_Voz = Av_Voz()
        Cadastro_Paciente = Cadastro_Paciente()
        Consulta = Consulta()
        Editar_Paciente = Editar_Paciente()
        Fatores_Desencadeantes = Fatores_Desencadeantes()
        Fatores_Relevantes = Fatores_Relevantes()
        Menu_Cadastro = Menu_Cadastro()
        Menu_Principal = Menu_Principal()
        Menu_Triagem = Menu_Triagem()
        Queixas = Queixas()
        
        '''Início do programa'''
        Menu_Principal_Func()
    
        sys.exit(app.exec_())

  • Qt Champions 2019

    @andre_sophia Please, next time make sure you mark your code as code properly to help others to read and understand your code. I fixed it this time for you.


  • Qt Champions 2019

    @andre_sophia said in Delay to open window after use my desktop app(open and close many windows), when more windows I open, larger will be the delay:

    Cadastro_Paciente = Cadastro_Paciente()
    Consulta = Consulta()
    Editar_Paciente = Editar_Paciente()
    Fatores_Desencadeantes = Fatores_Desencadeantes()
    Fatores_Relevantes = Fatores_Relevantes()
    Menu_Cadastro = Menu_Cadastro()
    Menu_Principal = Menu_Principal()
    Menu_Triagem = Menu_Triagem()
    Queixas = Queixas()

    Well, you create and keep your windows all the time.
    You should only create a window if you want to show it. And use Qt::WA_DeleteOnClose as @JonB suggested.



  • @andre_sophia
    One thing: I think you are re-connect()-ing all the time, setting up slots on signals again & again.

    E.g.

    def Menu_Cadastro_Func():
    	Menu_Cadastro.pushButton.clicked.connect(Menu_Principal_Func)
    
    def Menu_Principal_Func():
    	Menu_Principal.pushButton_3.clicked.connect(Menu_Cadastro_Func)
    

    Since you are closing (but not destroying/getting rid of) these windows all the time, the connect() will build up. ( @jsulm will correct me if I'm wrong, but I do not think Qt checks for an exact duplicate connnect() and skips it, I think it adds it again.) If that's right, then I think you start to show/hide (the same) windows multiple times the more you click around....



  • @jsulm I didn't know that, it's my first time here.
    Thanks, I'll do it!



  • @JonB said in Delay to open window after use my desktop app(open and close many windows), when more windows I open, larger will be the delay:

    @andre_sophia
    One thing: I think you are re-connect()-ing all the time, setting up slots on signals again & again.

    E.g.

    def Menu_Cadastro_Func():
    	Menu_Cadastro.pushButton.clicked.connect(Menu_Principal_Func)
    
    def Menu_Principal_Func():
    	Menu_Principal.pushButton_3.clicked.connect(Menu_Cadastro_Func)
    

    Since you are closing (but not destroying/getting rid of) these windows all the time, the connect() will build up. ( @jsulm will correct me if I'm wrong, but I do not think Qt checks for an exact duplicate connnect() and skips it, I think it adds it again.) If that's right, then I think you start to show/hide (the same) windows multiple times the more you click around....

    The problema was exatly That @JonB, Now I conncted the buttons only once, in the class definition, as below:
    bacd6d39-b6cf-49de-8f3e-de68bd9e4772-image.png

    thank you so much!!!



  • @andre_sophia
    Glad it solved. Yes, in the normal course do all your connect()s in the __init__(), after the setupUi(), so it's just once.