IIS 5 & IIS 6
Application Pool Crash
Last post May 02, 2008 06:10 PM by mshubat
Dec 13, 2007 07:54 AM|PraveenPoli|LINK
We are facing a problem with the following error message for a web application (ASP.Net 2.0) running on IIS 6.0
A process serving application pool 'AppPool' suffered a fatal communication error with the World Wide Web Publishing Service. The process id was '5448'. The data field contains the error number.
I used DebugDiag tool to debug and analyzed the dump file using the same tool. and I am seeing the Memory Heap corruption errors while connecting to some COM DLLs. (SAS 9.1.3)
In w3wp__PID__4940__Date__12_03_2007__Time_07_23_17AM__422__Second_Chance_Exception_C0000005.dmp the assembly instruction at ntdll!ExpInterlockedPopEntrySListFault in C:\WINNT\system32\ntdll.dll from Microsoft Corporation has caused an access violation exception
(0xC0000005) when trying to read from memory location 0x0004000d on thread 52
When I click on thread 52 it takes me to the following.
Thread 52 - System ID 488
Entry point SASWMan!DllUnregisterServer+b95d
Create time 12/3/2007 7:23:15 AM
Time spent in user mode 0 Days 0:0:0.0
Time spent in kernel mode 0 Days 0:0:0.0
Function Arg 1 Arg 2 Arg 3 Source
ntdll!ExpInterlockedPopEntrySListFault 04ff08f8 072ff4fc 7c82a0b8
ntdll!RtlAllocateHeap+14e 04ff08f8 05c8d3e0 0000005c
ntdll!RtlAllocateHeap+e2 04ff0000 00000000 0000005c
SASComb!DllCanUnloadNow+d705 0000005c 1001139a 0000005c
SASComb!DllCanUnloadNow+d727 05c89ab0 066183ec 00000001
SASComb+1d8f 05c89ab0 066183ec 065facac
SASWMan!DllUnregisterServer+89ef 072fff2c 04e74e60 04e74ce0
SASWMan!DllUnregisterServer+7ec0 0607ec44 00000000 00000000
SASWMan!DllUnregisterServer+b9bc 04e74d80 00000000 00000000
kernel32!GetModuleHandleA+df 04e45388 04e74d80 00000000
and the heap corruption is as below
Heap 58 - 0x04ff0000
Heap Name SASComb!DllCanUnloadNow+149924
Heap Description This heap is used by SASComb
Reserved memory 1.06 MBytes
Committed memory 596.00 KBytes (54.78% of reserved)
Uncommitted memory 492.00 KBytes (45.22% of reserved)
Number of heap segments 2 segments
Number of uncommitted ranges 1 range(s)
Size of largest uncommitted range 492.00 KBytes
Calculated heap fragmentation 0.00%
The DLLs listed above SASomb and SASWman are SAS DLLs and I am not sure whether this error is related to SAS or .netframework 2.0 or IIS or...
We already contacted SAS Support and couldn't get much help from them and all SAS DLLs are latest ones which we are using.
We are connecting to SAS on Unix server from .Net 2.0 framework using ASP.Net (using VB.Net) with IIS 6.0 on webserver.
Before migrating to 2.0 (in 1.1) we didn't face this issue, but this error is occuring after every 5 minutes after we converted to 2.0
Could you please help we have a release this weekend..and Thank you in advance.
Mar 09, 2008 07:31 PM|Luciano.cl|LINK
read this article
Mar 10, 2008 10:07 AM|ganeshanekar|LINK
Is this fixed or still happening?
This might be due to .NET 2.0 and as the default policy for unhandled exceptions has changed in the .NET Framework 2.0.
See this article for more details:
Unhandled exceptions cause ASP.NET-based applications to unexpectedly quit in the .NET Framework 2.0
May 02, 2008 06:10 PM|mshubat|LINK
What happens if you turn off "Enable rapid fail protection" on the app pool?