Slow load from CD or DVD

sierdzio

Do you load Qt dynamically? I would suspect it takes the OS a lot of time to load QtCore and - especially - QtGui. 2 things that might help here are:

make sure to deploy Qt release dlls (they are much, much smaller in size)
try to make them reside close to the application, so that CD/DVD head does not need to jump around too much

Alternatively, you can compile statically just to be sure.

Jeroentjehome

Well, The DVD/CD is much much much slower in operation then a HDD! It always is. So when having a complete program on a CD is will be hard to load into memory before execution. As sierdzio says is very much so. Make the program as small as possible by using the dynamic linked methode and copy the used dll's into the program dir on the CD. That might do the trick.
Greetz

ddolby

All the DLLs are in the same directory as the program, and the program is only 81KB so it is pretty small already. I am going to try the static compile option.

ddolby

I built Qt statically, and statically linked my app against it, and it didn't seem to make much difference.

DerManu

something is not right here. An 81 KiB file on CD should be loaded into memory nearly instantly. Even the ~12 MiB of the Qt so's should be in memory in no time.

Is it a modern CD drive (52x or something like that?), does other data of that magnitude copy fast to your HDD?

ddolby

Yes this has been run on a few different machines. All either i5 or i7 machines with modern DVD and Blu-Ray drives.

ddolby

Another strange behavior that is being is seen is the first time run from the DVD or CD there is a crash when you exit the application, but if you launch the application again,leaving the disc in and exit there is no crash.

ddolby

the crash was unrelated to this slowdown. I have resolved the crash.

huajin

do you have resolved the problem?

huajin

i have the same problem, can you help me?