Running desktop app takes too much time

Daniziz

Hi,

I have a problem with my qtcreator at home.

When I try to run my proyect, it takes like 1 minute or more to start my app. It doesn't take more than 10 seconds to do it at my job, so I have a feeling about graphic card problem. If I run my app from a terminal, it also takes too long.

The thing is, my home computer is like 1000 times better...

My specs:
Ubuntu 18.04.1 LTS
Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz
16GB RAM
NVIDIA GeForce RTX 2080 (Driver Version: 415.18)

My Qt Version:
Qt Creator 4.7.2
Based on Qt 5.11.2 (GCC 5.3.1 20160406 (Red Hat 5.3.1-6), 64 bit)

I'm going to try to downgrade NVIDIA drivers back to 410 (Its the only upgrade I've made) because it was ok then...

¿Could it be a bug?

Regards,

Dani.

Daniziz

Hi all,

I saw it!!!!!

@aha_1980 I did that, and I saw it was waiting for connection to a remote database server. So I decided to try @mrjj advice. I created a new project with no database connection and GUI showed me faster than light speed...

I made a little research and i found it was a reverse lookup problem with remote database server. I configured my connection to make my computer and database server more friendly and now its working fine!

thank you all!

mrjj

Hi
Does a plain new GUI project also take longer to start ?
Does your application uses openGL ?
It does sound like some incompatibility with new driver but if its its a real bug in Qt or something else
it hard to say at this point.

fcarney

In our organization we have noticed that Ubuntu 18.04 is less responsive than 16.04. We have chosen to stay with 16.04 for this reason. No idea if this is a factor in your situation. We also have no idea why 18.04 is this way. We have seen big performance problems in virtual machines and our target hardware.

Daniziz

Hi @mrjj

Hi
Does a plain new GUI project also take longer to start ? -No it doesen't, but mine is sooo much simple (1 window, 3 text boxes)
Does your application uses openGL ? -How do I check this?
It does sound like some incompatibility with new driver but if its its a real bug in Qt or something else
it hard to say at this point.

Going back to 410 didn't solve it... How can I see what is Qt doing since it shows me this:

Compile Output:

17:59:10: Running steps for project ReparacionesSIRA...
17:59:10: Configuration unchanged, skipping qmake step.
17:59:10: Starting: "/usr/bin/make" 
make: Nothing to be done for 'first'.
17:59:10: The process "/usr/bin/make" exited normally.
17:59:10: Elapsed time: 00:00.

Application Output:

17:59:10: Starting /home/diicic/proyects/CIC-Workflow/build-ReparacionesSIRA-Desktop_Qt_5_11_2_GCC_64bit-Debug/ReparacionesSIRA...

Regards,

aha_1980

@Daniziz I'd run the app through an profiler (you can do this from Creator) and see where the time is lost.

mrjj

Hi
I would also add 3 text boxes to the empty sample and see if it get slow then.

Does your application uses openGL ? -How do I check this?
Well you would know if you did then :)
Using any of the OpenGL classes or QML.

jsulm

@Daniziz said in Running desktop app takes too much time:

How can I see what is Qt doing since it shows me this

Do a complete rebuild. Best is to delete the build directory, run qmake and then build.

Daniziz

Hi all,

I saw it!!!!!

@aha_1980 I did that, and I saw it was waiting for connection to a remote database server. So I decided to try @mrjj advice. I created a new project with no database connection and GUI showed me faster than light speed...

I made a little research and i found it was a reverse lookup problem with remote database server. I configured my connection to make my computer and database server more friendly and now its working fine!

thank you all!

wrosecrans

@Daniziz If the startup time was consistently just a little over almost exactly 1 minute, that's almost always smells like a network timeout. Almost any round number like that is a good hint. Purely local stuff can have similar timeouts (Linux kernel defaults to 120 sec timeout on an i/o operation if it is talking to a broken hard drive, for example). But it is much more common to be some sort of network related issue. Just a little bit of trivia to keep in your pocket the next time you are debugging a similar weird startup delay.