[Interest] QJsonObject memory leak?

[Elvis Stansvik]

Can you create a standalone example? (I see no calls to your
create/uncreate)

How are you measuring memory consumption?

Elvis

Den tors 2 nov. 2023 16:52Nuno Santos <nuno.santos at imaginando.pt> skrev:

> Hi,
>
> I have realised that I cannot release all the memory allocated by a huge
> QJsonObject when I don’t need it any more. To ensure that nothing else was
> in between I have created a simple program that does what is below.
> Conclusion:
>
> - Running on a Mac, compiled in release with Qt 6.5.3
>
> - Starts with 31.7 MB
>
> [image: Screenshot 2023-11-02 at 15.48.29.png]
>
> - Goes up to 412.5 MB
>
> [image: Screenshot 2023-11-02 at 15.48.43.png]
>
> - After calling uncreate drops to 42.7
>
> [image: Screenshot 2023-11-02 at 15.48.50.png]
>
>
> If I repeat this procedure, it always increases the process memory size
> although it is not linear.
>
> In iOS the problem is even worse.
>
> Any ideas of what is happening here?
>
> Thank you!
>
> Best regards,
>
> Nuno
>
>
> QString GetRandomString()
> {
>     const QString
> possibleCharacters("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789");
>     const int randomStringLength = 4096; // assuming you want random
> strings of 12 characters
>
>     QString randomString;
>     for(int i=0; i<randomStringLength; ++i)
>     {
>         int index = QRandomGenerator::global()->generate() %
> possibleCharacters.length();
>         QChar nextChar = possibleCharacters.at(index);
>         randomString.append(nextChar);
>     }
>
>     return randomString;
> }
>
> void Controller::create()
> {
>     qDebug() << Q_FUNC_INFO;
>
>     for (int i=0; i<100000; i++)
>         _data[QString::number(i)] = GetRandomString();
> }
>
> void Controller::uncreate()
> {
>     qDebug() << Q_FUNC_INFO;
>
>     _data = QJsonObject();
> }
>
>
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