QT applications occupy CPU resources have been very high

Roy.Wang

In the Linuxs system ,Start a simple QT application without doing anything.CPU resources occupy almost 0 .
However, after the system sleep wakeup, the QT application CPU resources occupy a high, has been maintained at around 25%, can not go down !

As shown in the following figure

DvrUI is the QT application.
Don't let it CPU up so high ,How to deal with such problems?.

Charlie_Hdz

I don't remember having problems with resources in Qt Implementation.

Did you developed the "Qt application" or where did you get it?

BTW, being based in C++, Qt is intended to not take too much resources... Compared with Java and similars.

Kind Regards,

Carlos

jsulm

@Roy.Wang What is VideoPro? It is consuming 183% of your memory!
The high CPU usage of your app could be caused by your app constantly swapping memory RAM <-> disk, because all your RAM is occupied by VideoPro!

J.Hilk

@jsulm It consumes more memory than it's allowed to, sounds like something done in java
:D

jsulm

@J.Hilk Well, I guess it is 183% of physical memory :-)

mrdebug

dvrui maybe it is a gui program that display a video stream.
Really is there someone that writes a daemon software for embedded devices in Java?

ambershark

@Roy.Wang Does any other Qt application exhibit this same behavior? That would probably be more application based rather than a Qt thing.

I'm betting dvrui uses some type of hardware (just guessing based on it's name). So when the pc sleeps and shuts down that hardware, then comes back up, the application isn't deal with that loss and reacquire properly.

Totally guessing though. That's why you should test with any other Qt application to find out if it's dvrui or Qt.

Roy.Wang

@ambershark

DvrUI is a simple QT application without doing anything.

This happens in all QT applications

Roy.Wang

@jsulm VideoPro is a video program, I do not start it, DvrUI sleep back, will also have to occupy such a high CPU resources

DvrUI is a simple QT application without doing anything.No interfaces are called.

This happens in all QT applications

jsulm

@Roy.Wang Is it the same if VideoPro is not running?
"I do not start it" - it is running as you can see in your screen-shot.

Roy.Wang

@jsulm Yes

Roy.Wang

@jsulm it is the same if VideoPro is not running,
The DvrUI app, CPU resources occupy a high (25%).

jsulm

@Roy.Wang What is the device where you have this issue?

Roy.Wang

@jsulm a linux system device

J.Hilk

@Roy.Wang Thats as detailed of an Answer as "A blue one" is to the question "What car do you drive?"

ambershark

@Roy.Wang said in QT applications occupy CPU resources have been very high:

@ambershark

DvrUI is a simple QT application without doing anything.

This happens in all QT applications

What other Qt applications have displayed that behavior? Are you sure it's all of them, or just the dvr related ones that you have tried?

Also can you run an strace and see what they are doing that is using the high amount of cpu? That should help in tracking it down.

Qt obviously isn't designed to do that and it seems specific to your machine, so maybe strace can give us an idea of what is causing the cpu to spin like that.