Re: multi-threading fundementals?
runcyclexcski@yahoo.com wrote:
I guess I need a suggested reading, or a general advice to point me in
the right direction.
I am building an MFC .NET app that gets data from two cameras
simultaneously and intergrates the two signals. The interface with
camera 1 is working (sort of), and I am currently setting up
simultaneous communication with camera 2 from the application that
already can run camera 1.
Camera 2 came with its own sample manufacturer-written application and
a source code. Running the manufacturer's application in parallel with
my camera 1 application does not cause any performance issues.
So I took the source code supplied by the manufacturer of camera 2 and,
essentially, dumped it into a UIthread object within my camera 1
application. Doing so has significantly slowed down data processing of
both camera 1 and 2. I need to fundamentally understand why: running
the 2 cameras in two independent applications did not cause any
problems.
A possible explanation: Threads block each other (due to internal
synchronization) if a thread attempts any operation on a window created
in another thread. Review your code for any such cross-thread access to
windows/controls. Cross-thread parent-child relationships between
windows also have such issues. To get the performance you got with two
applications you have to limit each thread to touching its own windows
only, and these windows must be independent of windows created in other
threads.
--
Scott McPhillips [VC++ MVP]