NT Crash

[poseidon_sthlm]

Hello!

I'v have had several NT crashes since yesterday.
My Windows log:

Version=1
EventType=APPCRASH
EventTime=130491931139162871
ReportType=2
Consent=1
UploadTime=130491931139630872
Response.BucketId=39162846
Response.BucketTable=20
Response.type=4
Sig[0].Name=Application Name
Sig[0].Value=NinjaTrader.exe
Sig[1].Name=Application Version
Sig[1].Value=7.0.1000.14
Sig[2].Name=Application Timestamp
Sig[2].Value=51c1e199
Sig[3].Name=Fault Module Name
Sig[3].Value=KERNELBASE.dll
Sig[4].Name=Fault Module Version
Sig[4].Value=6.1.7601.18409
Sig[5].Name=Fault Module Timestamp
Sig[5].Value=5315a05a
Sig[6].Name=Exception Code
Sig[6].Value=[COLOR=Red]e053534f[/COLOR] ("soft stack overflow" raised by the CLR)
Sig[7].Name=Exception Offset
Sig[7].Value=000000000000940d

This crash occurs either when I relaod NinjaScript on a chart after I have modified and compiled a specific indicator or when I start NT and this indicator is attached to a chart in the open workspace. The indicator is huge (25 000 lines), but the development has worked fine for several month until yesterday. The crash occurs regardless if this indicator draws any objects on the chart or not. This problem seems intermittent since NT suddenly stopped crashing yesterday eavening when I was working on this indicator but then started to crash again when I opened NT this morning. What can I do?

Best Regards
posedon_sthlm

[NinjaTrader_Bertrand]

poseidon_sthlm, we would need to isolate and find out from which condition / section exactly the issue arises. So I would ask you to look into what changes you have done recently to the study around the time the issue started to manifest. Also you seem to be using the outdated R14 release on this machine in your testing still? Would upgrading to latest R24 of NT7 have any effect on the outcomes seen?

[Harry]

You need to debug your indicator. Also have a look at the NinjaTrader log and trace files. If you are lucky you will find an error message somewhere.

[poseidon_sthlm]

The reason for my NT crashes may be a custom method in another added indicator (indicator on indicator) that is called several times by the main indicator. (The method is also called in a loop from the main indicator). Is it possible that this method hasn't finished the calculations from a prior call when it is called anew, and that this causes a crash when NT is calculating the indicator for the historical bars on the chart? If this is a valid assumption, how can I prevent this situation? How can I prevent that the method is called a second time before it has returned the result for the first call?

Best Regards,
poseidon_sthlm

[NinjaTrader_Bertrand]

Hi poseidon_sthlm, unless you have introduced custom threading that should not be a plausible scenario since it could not happen under the default NT7 threading as your NinjaScript would run on one thread. The stacktrace would not be very helpful to pinpoint, we would suggest adding try / catch statements throughout your code isolating the functional groups and then log the exception details to understand better. Another 'last resort' thought would be attaching your study to the VS debugger to see if more granular details could be traced this way when this issue unfolds.

[poseidon_sthlm]

Is is safe to close NT and then delete the files in the folder: \NinjaTrader 7\cache ?

/poseidon_sthlm

[NinjaTrader_Bertrand]

Yes, would be rebuilt next time you open your NS editor.

[poseidon_sthlm]

Is it possible that the condition (CurrentBar == -1) can be true for any situation when NT calculates the historical indicator values for a chart when I reload NinjaScript?

[NinjaTrader_Bertrand]

I would not expect that, since CurrentBar would not make any historical vs realtime distinction. 0 would be your leftmost bar and then it would build up until right most bar is reached. Single vs MultiSeries scripts will have a bit different processing as single series would always process to the current visible bar only, while MultiSeries would work through all bars regardless.

[poseidon_sthlm]

After many, many hours of trouble shooting I belive that I have found a clue to where to look for the cause of my NT crashes. The crash only occurs in the 64-bit NT version but not in the 32-bit version. I have been using the 64-bit version for a long time and haven't experienced any issues until now.

The crash occurs when NT (64-bit) is recalculating historical indicator values for a chart when I do "Reload Ninjascript". My indicator is calculation intensive since I copied all my custom indicators into one indicator file. (For computation efficiency reasons I only want one instance of each referenced indicator created.) I use the c# classes Collections.Generic and Linq and I shuffle a lot of data in several custom structs in several generic List(T) and IEnumerables.

I have reviewed my entire code thorough and isolated every part of it. (And I do have eliminted possible unwanted deferred execution issues). The try-catch blocks do not cast any error messages. I mentioned above that the issue seemed intermittent. Once NT succeeds to calculate the historical values the issue disappears . I suppose that this is because the indicator historiy is cahced and reused the next time you do "Reload ". But the strangest thing is that no matter what part of the code I do eliminate (with if (false){} ) , as long as it is large enough, the issue diasppears. So it seems to me as if I hit some CPU threshold. When I filter for NT in the Resource Monitor in Windows it shows that the frequency is 109% before NT crashes.

I do want to use the 64-bit NT version for obvious reasons. How can I continue to solve this issue?

Best Regards
posedon_sthlm

[NinjaTrader_Bertrand]

posedon_sthlm, I have reviewed with development and from the stack trace they feel the issue arises from a too deep recursive call of your custom methods / properties used in the script.

Some background would be for example explained here - http://joel.inpointform.net/software...tack-overflow/

If you're having access to a debugger or profiler that would likely be helpful to see exactly where most of your time / memory is spend while the code executes.

[NinjaTrader_Bertrand]

Another thought would be looking into converting code to use methods that would use the heap instead of the stack (value types vs reference types).

[poseidon_sthlm]

Can you recommend a debugging software that is affordable and doesn't have a steep learning curve? I'm not a programmer, just a NT amateur developer (as you may already have guessed).

I want to clarify that the structs that I use in my indicators are just simple instance constructors that I use to model TA patterns. I have declared all my structs in the 'myCutomIndicatorMethods' file. Some of these structs implement the interfaces IComparer<T> and IEquatable<T>. I have not created any other advanced custom methods related to these structs. (But I do use the maxBy()/minBy() Linq extension methods in the MoreLinq namespace created by Jon Skeet.) Do you think that the use of classes instead of structs for the instance contstuctors in my case would substantially lower the use of the stack? (Code example below)

I still find it strange that my indicator runs flawless in the 32-bit NT version but crashes in the 64 bit version. How can this be?


Should I replace this in the 'MyCustomIndicatorMetods' file:

#region DataPoint : IEquatable<DataPoint>
                
                public [COLOR=Red][B]struct[/B][/COLOR] DataPoint : IEquatable<DataPoint>
                {
                    public int barNo;
                    public double value;
                                
                    public DataPoint(int dpBNo, double dpV)
                    {
                        this.barNo = dpBNo;
                        this.value = dpV;
                    }
                    
                    
                    #region Equals()
                    
                    public bool Equals(DataPoint other) 
                    {
                        if (this.barNo.Equals(other.barNo)
                            && this.value.Equals(other.value) )
                        {
                            return true;
                        }
                        else 
                        {
                            return false;
                        }
                    }

                    // Override Object.Equals(object)
                    public override bool Equals(object obj)
                    {
                        if ( obj is DataPoint)
                        {
                            return this.Equals((DataPoint)obj);
                        }
                        else 
                        {
                            return false;
                        }
                    }  
                    
                    
                    public override int GetHashCode()
                    {
                        int hashValue     = this.value.GetHashCode();
                        int hCode         = this.barNo ^ hashValue;
                        return hCode.GetHashCode();
                    }
                    
                    
                    public static bool operator == (DataPoint d1, DataPoint d2)
                    {
                        return d1.Equals(d2);
                    }

                    
                    public static bool operator != (DataPoint d1, DataPoint d2)
                    {
                        return ! (d1.Equals(d2));
                    }
                    
                    #endregion
                
                }
                
                #endregion

... with this?

#region DataPoint : IEquatable<DataPoint>
            
            public [B][COLOR=Red]class[/COLOR][/B] DataPoint : IEquatable<DataPoint>
            {
                public int barNo;
                public double value;
                
                // Default Constructor
                public DataPoint()
                {
                    barNo = -1;
                    value = -1.0;
                }
                
                public DataPoint(int dpBNo, double dpV)
                {
                    this.barNo = dpBNo;
                    this.value = dpV;
                }
                
                
                #region Equals()
                
                public bool Equals(DataPoint other) 
                {
                    if (other == null)
                    {
                         return false;
                    }
                        
                    if (this.barNo.Equals(other.barNo)
                        && this.value.Equals(other.value) )
                    {
                        return true;
                    }
                    else 
                    {
                        return false;
                    }
                }

                // Override Object.Equals(object)
                public override bool Equals(object obj)
                {
                     if (obj == null)
                    {
                         return false;
                    }
                    
                     // If parameter cannot be cast to DataPoint return false.
                    DataPoint dataPointObj = obj as DataPoint;
                    
                    if ( dataPointObj == null )
                    {
                        return false;
                    }
                    else 
                    {
                        return Equals((DataPoint)obj);
                    }

                }  
                
                
                public override int GetHashCode()
                {
                    int hashValue     = this.value.GetHashCode();
                    int hCode         = this.barNo ^ hashValue;
                    return hCode.GetHashCode();
                }
                
                
                public static bool operator == (DataPoint d1, DataPoint d2)
                {
                    if ((object)d1 == null || ((object)d2) == null)
                    {
                         return Object.Equals(d1, d2);
                    }
                    
                    
                    return d1.Equals(d2);
                }

                
                public static bool operator != (DataPoint d1, DataPoint d2)
                {
                    if (d1 == null || d2 == null)
                        return ! Object.Equals(d1, d2);

                    return ! (d1.Equals(d2));
                }

                #endregion
            
            }
            
            #endregion

Best Regards,
poseidon_sthlm

[NinjaTrader_Bertrand]

poseidon_sthlm, 32 vs 64 bit would definitely have internally differences in memory management so I would not be surprised seeing those manifest in your scenario. First thing you could look into is attaching to the Visual Studio Express debugger (newer version have an attach to option now) - https://www.ninjatrader.com/support/..._debugging.htm. Moving from the struct to the class (reference type) should free up the heap, yes.