Re: Background thread with lower priority



Hi Chris,

Thanks for your reply. I guess my question was not clear enough.

It's not the GC that causes the non-responsiveness. My assumption is that
the non-responsiveness is caused by running my background sync on a thread
with the same priority as the main thread. So when the background sync
starts, both the UI and the sync are competing for the CPU cycles, right?

That's the reason I started creating my own thread and setting the priority
lower than the main thread. However, the blog post from Daniel Moth gives me
some concerns because it discourages changing the priority of a thread
because of unexpected behavior (mentioning the garbage collection). At
least, that is my understanding of the article.

So maybe my question should be: is it ok to have a background thread running
on a lower priority so not to interfere with the GUI, or does running on
lower priority have unexpected side effects (like mentioned in the article)
and should be avoided?

Thanks,

--
Jeffry van de Vuurst
CWR Mobility
www.cwrmobility.com
--
"<ctacke/>" <ctacke[@]opennetcf[dot]com> wrote in message
news:%23hmTTPTHHHA.2632@xxxxxxxxxxxxxxxxxxxxxxx
If a GC occurs, all threads in the process are suspended. Doesn't matter
what priority any of the threads are.

Are you sure it is a GC that's causing the non-responsiveness?


--
Chris Tacke
OpenNETCF Consulting
Managed Code in the Embedded World
www.opennetcf.com
--


"Jeffry van de Vuurst" <jeffry.cwrmobility@xxxxxxxxxxxxxxxxx> wrote in
message news:eNdHtCTHHHA.4712@xxxxxxxxxxxxxxxxxxxxxxx
Hi,

I have a CF 2.0 app that uses 2 background threads. 1 for polling for a
network connection and 1 for performing a background sync.

First I used the OpenNETCF BackgroundWorker for this purpose. However,
when performing a background sync the UI became unresponsive. Now I
changed it to a regular thead using:
Thread backgroundSyncThread = new Thread(DoBackgroundSync);
backgroundSyncThread.Priority = ThreadPriority.Lowest;
backgroundSyncThread.IsBackground = true;
backgroundSyncThread.Start();

However, I read here
http://www.danielmoth.com/Blog/2004/08/threads-and-threadpriority-with-net.html,
that chaging the priority of threads may be risky because garbage
collection could run on the low priority thread.

It's an article from August 2004 but does mention CF 2.0 beta 1. Does
this still apply? And if so, what are other ways to make sure that the
(potentially long) running background thread doesn't freeze the UI? Is
doing a Thread.Sleep(0) from the worker thread effective? I've read
different stories about the effectiveness of Thread.Sleep(0)...

Thanks,

--
Jeffry van de Vuurst
CWR Mobility
www.cwrmobility.com
--






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