[Interest] Optimizing performance with hundreds of widgets

[Viktor Engelmann]

Am 15.02.2017 um 18:28 schrieb Gibbs, Matt:
> Hi All,
>
> I’m working on a Qt-based project to display rapidly updating information from a control system.  I want to display hundreds of signals, each updating at about 10 Hz.  As a performance test, I’ve thrown 500 Labels in a grid layout, and fire a timer every 100 ms which calls setText on each label.  This ends up being surprisingly CPU-intensive: on reasonably modern hardware (2012 MacBook Pro), I use 70% of one CPU.  This doesn’t leave me much overhead to do anything else.
>
> Are there any best practices to reduce CPU usage in this case?
>
> Cheers,
> —Matt
>
> Matt Gibbs
> SLAC Accelerator Operations Group
> mgibbs at slac.stanford.edu
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you might want to do

   setUpdatesEnabled(false);
   // do your updates
   setUpdatesEnabled(true);

-- 

Viktor Engelmann
Software Engineer

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