Hi Harri! I ran into similar issues with my latest embedded project. The solution was to use QML Loader elements to postpone loading.
Greetings, Frank. On 06/14/2012 08:46 AM, Harri Pasanen wrote: > On 06/13/2012 11:07 PM, Till Oliver Knoll wrote: >> Am 13.06.12 22:03, schrieb Harri Pasanen: >>> I started working on a bit more substantial QML application for symbian >>> and ran into some issues. One of these is the startup time with 10+ QML >>> non trivial files, and I'm not finished adding them. >> Wait a sec... what is a QML file, what does it contain? That's a simple >> "page" (window, dialog, ...) with buttons etc. on some mobile phone >> application, including animations and resources and some JavaScript >> logic, right? > Pretty much so. Mainly UI stuff, most logic I already have in C++. > >> So are you saying you already start hitting performance limits with a >> simple "10 pages application"? Doh! >> >> (Sorry when I say "simple" here - I'm trying to imagine how that should >> work out with *dozens* of dialogs and windows for a *medium* sized >> desktop application!) > As a rule of thumb I account for the mobile phone version being ~20 times > slower than my Core i7 desktop. So if my application starts up in .5 seconds > on desktop, it will take 10 seconds on the phone. (That would be 1.3GHz > ARM11, or 1GHz ARMv7.) > > For most phone apps 10 seconds is not acceptable, but usually that can > be worked around by using lazy loading, so the 10 secs is hidden away in > a longer period. > >> So I guess that's Qt 4.x? So any hope things will improve with Qt 5.x? >> Or is this an "initial parsing/compiling" problem where even the latest >> of greatest OpenGL ES 2.0 requirement that we already have and V8 >> whatever JS optimisation engine can't help? :0 > I suspect this is initial parsing/compiling. Part of the issue is > probably slower I/O, actually going to flash, opening files, reading > etc. I haven't done rigorous profiling yet. Also I haven't tried with > Qt 5. > > Btw. does V8 use the JIT on mobile? Is it selectable? > > Harri > _______________________________________________ > Interest mailing list > Interest@qt-project.org > http://lists.qt-project.org/mailman/listinfo/interest _______________________________________________ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
