Windows client is freezing

michaelk

Hello there,

we have the following problem: When calling PAGE.RUNMODAL it can from a higher number of users (> 6), that all clients that are logged on to the same service freeze for about 2 minutes. During this time it is not possible to log on to this service. After that, everything continues as normal as if nothing had happened.
We've already checked the time synchronization. We have also changed the following value:
<add key = "ClientServicesKeepAliveInterval" value = "300" />
the NST and SQL Server running on a VMWare
In the Event Viewer is the following:
Source: mscorlib
HRESULT: -2146232828

---

Type: Microsoft.Dynamics.Nav.Types.Exceptions.NavSessionTerminatedException
Message: The server session (ID: 220) stopped due to a request for stopping the session.
StackTrace: at Microsoft.Dynamics.Nav.Runtime.SessionAccessLock.ThrowSessionTerminatedException () at Microsoft.Dynamics.Nav.Service.ServiceCall.GetClientReturnValue (Action invokeCallback) at Microsoft.Dynamics.Nav.Service.NSClientCallback.FormRunModal (NavForm shape parameter NavFormRuntimeParameters ) record at Microsoft.Dynamics.Nav.Runtime.NavForm.RunModal (NavRecord, Int32 FieldNo) at Microsoft.Dynamics.Nav.Runtime.NavForm.RunModal (Boolean isInLookupTrigger, Boolean isLookup, Int32 formid, NavRecord record, Int32 FieldNo) at Microsoft .Dynamics.Nav.Runtime.NavForm.RunModal (Boolean isInLookupTrigger, Boolean isLookup, Int32 formid, NavRecord record) at Microsoft.Dynamics.Nav.BusinessApplication.Codeunit50000.ShowProductionBOMNo_Scope.OnRun () at Filter.InvokeWithFilter (NavMethodScope) at Microsoft.Dynamics .Nav.BusinessApplication.Codeunit50000.ShowProductionBOMNo (INavRecordHandle itemVar) at Microsoft.Dynamics.Nav.BusinessApplication.Codeunit50000.OnInvoke (Int32 MemberID, Object [] args) at Microsoft.Dynamics.Nav.BusinessApplication.Page99000789.a60Action1000000004a62_a45_OnAction_Scope.OnRun() at Filter.InvokeWithFilter (NavMethodScope) at Microsoft.Dynamics.Nav.BusinessApplication.Page99000789.a60Action1000000004a62_a45_OnAction ()
Source: Microsoft.Dynamics.Nav.Ncl
HRESULT: -2146233088
The customer uses NAV 2013 R2 CU 27 Build 43896
Has anyone of you an idea what's wrong.

Microsoft doesn't have an idea what can it be.

yours

Michael

manisharma31

try to disable VMtool services and check.

manisharma31

try to disable VMtool services and check.

michaelk

Hello,

we have discovered that the Problem is the value "MaxConcurrentCalls". When the value of calls is reach the Maximum trought Page.Runmodal call than the Client and the NST is freezing.

Phenno

Do you mean MaxConcurentCalls or MaxConcurrentConnections?

MaxConcurrentCalls is, by default MaxValue, so I'm curious why would you change this setting?

Phenno

My mistake, I was refering to NAV 2015. On NAV2013, MaxConcurentCalls is 40, by default.

michaelk

Hello Phenno,

I can nowhere see that this value is set to MaxValue. Nowhere in NAV 2015 or NAV2016.

Phenno

Wow, indeed it says default: 40...

https://msdn.microsoft.com/en-us/library/dd355055(v=nav.80).aspx

I always thought this setting is default to MaxValue.

Does this setting limits concurrent calls from one client session or for any client sessions? Why would this be set to 40 by default?

michaelk

Hello Phenno,

this Setting Limits concurrent calls for all users. I don't know why I is set to 40. Maybe because 40 concurrent calls on the same NST is imprombable. But if you know that every Page.Runmodal is a new call and there is a Page which is call by his own in Runmodal mode than the number of 40 can be to few.

Phenno

I suppose then that purpose od setting is to protect NST from bad programming that could cause uncontrolled runmodals or similar calls.

michaelk

Yes this could be but the effect if the max number of calls is reach is very bad, because the hole nst is frozen. No one could work who are connectet to this nst and now one could connect to this nst.

Phenno

It is reproducable with pages but not with reports, even with requestpage. Anyway, I created page that calls itself for 45 times and my sessions got stuck for few minutes after which connection was down. Also tested separated clients opening 20 pages and on third client run all clients freezed. Two first clients lost connection but third one survived.

michaelk

Yes this is the same effect es we have. The easiest way to reproduce this Scenario is to set the value of MaxConcurrentCalls to 1. If you do this than you can start the Client but no page.runmodal Action is possible.

Phenno

Does that include navigation through pages opened from flowfields? User can open several pages in a row while navigating through data sometimes...