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Synchronization threads in subscription in live mapping
19 Feb 2015 12:23 #2811
by support
Replied by support on topic Synchronization threads in subscription in live mapping
If it's working, then it is probably right 
I haven't even expected it to be that simple.
The base implementations (in SynchronizationContext class) look like this:
I think that you should therefore use directly the delegate for your Post(...), because the original implementation can basically "get around" your lock by running the delegate from a thread pool thread - at any time, and without you being able to protect against it.
I haven't even expected it to be that simple.The base implementations (in SynchronizationContext class) look like this:
public virtual void Send(SendOrPostCallback d, Object state)
{
d(state);
}
public virtual void Post(SendOrPostCallback d, Object state)
{
ThreadPool.QueueUserWorkItem(new WaitCallback(d), state);
} I think that you should therefore use directly the delegate for your Post(...), because the original implementation can basically "get around" your lock by running the delegate from a thread pool thread - at any time, and without you being able to protect against it.
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18 Feb 2015 23:07 #2806
by miron
Replied by miron on topic Synchronization threads in subscription in live mapping
Could you check my implementation:
Remarks
1. I have used default synchronization context to derive main functionality:
QuickOPCSyncContext : SynchronizationContext
I hope that is ok.
2. set up in main thread:
var synchContext = new QuickOPCSyncContext();
SynchronizationContext.SetSynchronizationContext(new QuickOPCSyncContext());
(Quick opc thread)
3. In logic loop I would like to use property
lock(synchContext.SynchObject )
{
}
4. Should execute base method:
base.Post(d,state);
or should I execute "d" delegate
d(,state);
I have made small test and it's look that is working.
But I would like take knowledge in the origin.
Thank you, and qood night.
I am waiting for quick answer.
public class QuickOPCSyncContext : SynchronizationContext
{
public object SynchObject {get;set;} //tu use construction with lock
public QuickOPCSyncContext()
{
SynchObject = new object();
}
public override void Post(SendOrPostCallback d, object state)
{
lock(SynchObject)
{
base.Post(d,state);
//or just execute d(,state);
}
}
public override void Send(SendOrPostCallback d, object state)
{
lock(SynchObject)
{
base.Send(d,state);
//or just execute d(,state);
}
}
};
Remarks
1. I have used default synchronization context to derive main functionality:
QuickOPCSyncContext : SynchronizationContext
I hope that is ok.
2. set up in main thread:
var synchContext = new QuickOPCSyncContext();
SynchronizationContext.SetSynchronizationContext(new QuickOPCSyncContext());
(Quick opc thread)
3. In logic loop I would like to use property
lock(synchContext.SynchObject )
{
}
4. Should execute base method:
base.Post(d,state);
or should I execute "d" delegate
d(,state);
I have made small test and it's look that is working.
But I would like take knowledge in the origin
.Thank you, and qood night.
I am waiting for quick answer.
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