In Go, a call to the net.Listener type's Accept method returns an error. However, is there a way to tell the difference between a transient error (ie, this connection failed to set up) vs a permanent error (ie, the listener is dead, such as a Unix domain socket file that was forcibly removed)? If I can't tell the difference, I run the risk of infinite looping and spitting out errors as fast as I can since each Accept call will immediately return an error.
Figured it out. Errors returned by the net package may be of the net.Error type, which defines the Temporary() bool method which reports whether the error is temporary.
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Suppose we have the following situation:
launch_kernel_a<<<n_blocks, n_threads>>>(...);
launch_kernel_b<<<n_blocks, n_threads>>>(...);
cudaDeviceSynchronize();
if(cudaGetLastError() != CudaSuccess)
{
// Handle error
...
}
My understanding is that in the above, execution errors occurring during the asynchronous execution of either kernel may be returned by cudaGetLastError(). In that case, how do I figure out which kernel caused the error to occur during runtime?
My understanding is that in the above, execution errors occurring during the asynchronous execution of either kernel may be returned by cudaGetLastError().
That is correct. The runtime API will return the last error which was encountered. It isn't possible to know from which call in a sequence of asynchronous API calls an error was generated.
In that case, how do I figure out which kernel caused the error to occur during runtime?
You can't. You would require some kind of additional API call between the two kernel launches to determine the error. The crudest would be a cudaDeviceSynchronize() call, although that would serialize the operations if they actually did overlap (although I see no stream usage so that is probably not happening here).
As noted in comments -- most kernel runtime errors will result in context destruction, so if you got an error from the first kernel, the second kernel will abort or refuse to run anyway and that is probably fatal to your whole application.
Consider the following basic structure of a Parallel Convoy pattern in BizTalk 2016. It is a Parallel Action with 2 active Receive shapes. Combined with a single correlation set that is being initialized by both active receives.
Now my issue arose when I want to have separate exception handling, one for the left receive, and one for the right receive. So I've put a scope around the left receive (Scope_1) with a timeout. And I've wrapped that scope in another scope (Scope_3), to catch the timeout exception.
Now for some reason this isn't allowed and I get back "fatal error X1001: unknown system exception" at build time.
However, if I wrap the scope_3 around both active receives, it's building successfully:
What's the significant difference here for BizTalk to not allow separate timeout exception handling in this scenario?
By the way:
It doesn't matter what type of exception I'm trying to catch, or if all my scopes are a Long Running transaction or not, the occurrence of the error is the same.
If I make a separate correlation set for each receive, the error does not occur, but of course that's not what I want because it wouldn't make it a parallel convoy then.
Setting scopes to synchronized does not affect the behavior.
The significant difference is that the Orchestration will start up when it receives the first message, which may not be the scope_1. So the timer would not be started in that scenario. And if it was scope_1, well it won't time out as you have received it, but it won't be timing out for scope_2.
Having the timer around both, does set the timeout in both scenarios.
What you could do is have the timeout scope as per your second example and set a flag to indicate which one was received, and use that in your exception block.
The other options is a first Receive shape that initializes the correlation set, and then a second receive after it that has the following correlation and have the timeout on that.
First, i am able to replicate your issue.
Although visual studio reported this as an unknown system exception but for me it looks unreachable code detected based the receive shape that is inside the scope (scope_3) that is trying to initialize your correlation. So there's a possibility that you wont be able to initialize the correlation same way your left scope (scope_2) does if your main scope (scope_1) is having some exceptions.
The only way I can think is to use using different correlation sets, you can set your send port to follow on these correlation set.
Without using correlation sets, this should not give error during build time. For me this is considered to be an MS bug, VS should be able to point out the unreachable code detected, not fatal error:
After doing some refactoring to my WF4 service, I got this exception when calling some of the operations:
The execution of the InstancePersistenceCommand named {urn:schemas-microsoft-com:System.Activities.Persistence/command}LoadWorkflowByInstanceKey was interrupted by an error.
My xamlx file contains a few receive/sendreplytoreceive pairs, as shown below. The exception sometimes happens on receive2, sometimes receive3.
receive1 (no correlation, cancreateinstance=true)
send reply to receive (initializes content correlation on generated ID)
receive2 (correlates on ID, cancreateinstance=false)
send reply to receive
receive 3 (correlates on ID, cancreateinstance=false)
send reply to receive
After doing a lot of debugging and making sure all correlations where set up right, the exception disappeared for new instances of the workflow.
What does the exception mean, and why did it show up and why did it dissappear all of a sudden? Is it a code/xamlx issue or something with the infrastructure (AppFabric/SQL)?
I'm hosting the WF service with IIS/AppFabric, using AppFabric' SQL persistence.
According to this support note this error can be the result of a race condition between the Receive and a Delay activity expiring. Is this possible in your workflow.
I kinda figured mine out... aparently if you point your persistance store in a SQL previous to 2012 you get the error... so all i had to do is put mine persistance store in a SQL 2012...
When I had this problem it turned out to be a mistake in my connection string when instantiating the persistence store object.
SqlWorkflowInstanceStore store = new SqlWorkflowInstanceStore(connStr);
I realise this an old question but fixing the connection string got rid of my error while running store.Execute() so I thought I'd share!
I'll try provide as much information as possible:
No error message.
The instance stays in the "ready service instances".
The receive location has the same parameters (except URI, the three polling queries, user account/pw and receive pipeline) as another receive location that points to another database/table which works.
The pipeline is waiting for the correct schema.
The port surface and receive location are both waiting for the correct schema.
In my test example, there are only 10 lines being returned.
The message, which contains those 10 lines, validates against the schema.
I tried to let the instance alone to no avail - 30+ minutes - and no change in its condition.
I had also tried suspending and then resuming it which then places the instance in the "dehydrated orchestrations" list. Again, with no error message.
I'm able to get the message by looking at the body of the message that's in the "ready to run" service. (This is the message that validates versus the schema I use in Visual Studio.)
How might something like this arise?
Stupid question, but I have to ask... Is the corresponding host instance running?
I've got to invoke a RPC service, and all the parameters sent are String. It works quite well when the data is relatively small, but when one of the string grows to the size about 10 or over hundred KB, immediately after the service is invoked, it goes to the error handler:
[FaultEvent fault=[RPC Fault faultString="Error #2006: The supplied index is out of bounds." faultCode="InvokeFailed" faultDetail="null"] messageId="85CF2FB3-E79D-779F-87F9-B04520318D3A" type="fault" bubbles=false cancelable=true eventPhase=2]
And the server side still got invoked, and when it returns the result, error raised:
Error: Command already finished executing: [object AsyncTokenCommand]
Google says error #2006 may because of too many hierarchy levels, which seems impossible to me because all my parameters are string. And I also don't have the chance to mistake on index.
I first thought it was because the string sent is too long, I segmented it and sent in a list, but didn't work.
Thanks in advance if you guys can give any help.
Finally got it right.
It was because I turned on the Network Monitor in Flash Builder.
Everything OK after it's off.