PDF export heat up i.mx6
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Hi,
i use an i.mx6 cpu with linux os for a qt5.4.1 application.
In this application i use the following function to export some html pages to pdf files.bool PdfExport::exportFile(const char *path) { QWebPage page; page.mainFrame()->setHtml(exportString().c_str()); // printer is a QPrinter member variable of the PdfExport class printer->setPageMargins(5, 5, 5, 5, QPrinter::Millimeter); printer->setOutputFileName(path); printer->setPageSize(QPrinter::A4); printer->setPrintRange(QPrinter::AllPages); page.mainFrame()->print(printer); return true; }As long as i do not call the function, my cpu has a constant temperature of 45°C (CPU load ~35%).
But after i call it the temperature rise quickly to around 60°C, stays there and does not went down any more. Even if i wait an hour or so. CPU usage is furthermore at ~35%.
I think the GPU will heat up the chip, but why? My function does not hang and returns in a split second. -
Here http://forum.solid-run.com/linux-on-cubox-i-and-hummingboard-f8/temperatures--t490.html
I found the information that 85-90 degree is normal for that CPU.
How long do you wait before you execute exportFile()? Maybe 60 degree is normal. -
I have waited different times. The longest was around 1 and a half our, and the temperature was never higher than 45°C.
Then i call the export function and the temperature rise up to 60°C in less then 20 seconds and stays there until i close my application. If my application is not running and the os is idle the temperature is around 38°C.So 60°C is definitely not normal.
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Perhaps your printer object has been stuck in a loop of some sort. You could delete the printer after printing and see what happens. Perhaps printer could be a local in that function and be deleted automatically when not needed anymore, but you are best in thinking of such architectural questions.
