Re: stable driver for multithreaded environment (IIS 5.X)

While I am not an ODBC developer, my first inclanation would be to examine
your code for areas where you may be using the same connection resources
across multiple threads.


> hello,
>
> i've been making load-tests with Microsoft IIS 5.0 on Windows 2000,
> accessing postgresql via the Microsoft "OLEDB over ODBC" Driver using
> Postgres ODBC 7.03.0200.
> MDAC Version is 2.7 SP1 refresh.
> This version seems to have stability problems in a multithreading
> environment, same problems occur using version 7.03.0100:
>
> 1. the first bytes of column-data are corrupted under heavy load on the
> webserver machine
> 2. after some minutes of testing, the webserver starts blocking threads
> because of unhandled MDAC errors.
> Here is a stack-dump of one of the blocked threads:
>
> Warning: This thread is blocked by a Message Box
> Message Box Text: Runtime Error!
>
> Program: C:\WINNT\system32\dllhost.exe
>
> R6025
>
> - pure virtual function call
>
>
>
> Thread Type: MDAC Error being handled.  Possible ASP page
> Executing Page: R:\INETPUB\XXXX\SHOP\FOLDER.ASP
>
>  # ChildEBP RetAddr
> 00 0202d99c 77e234d6 USER32!NtUserWaitMessage+0xb
> 01 0202d9d0 77e33f21 USER32!DialogBox2+0x216
> 02 0202d9f4 77e23fdd USER32!InternalDialogBox+0xd1
> 03 0202dcac 77e24379 USER32!SoftModalMessageBox+0x752
> 04 0202ddf4 77e23871 USER32!MessageBoxWorker+0x247
> 05 0202de4c 77e24104 USER32!MessageBoxExW+0x77
> 06 0202de7c 77e232a2 USER32!MessageBoxExA+0xa0
> 07 0202de9c 7800bec3 USER32!MessageBoxA+0x49
> 08 0202debc 78007e22 MSVCRT!__crtMessageBoxA+0x81
> 09 0202e09c 78007f87 MSVCRT!_NMSG_WRITE+0x11f
> 0a 0202e0a4 7800bc7a MSVCRT!_amsg_exit+0x25
> 0b 0202e0ac 1f33f360 MSVCRT!_purecall+0x7
> 0c 0202e0b4 1f334aaf msadce!CSingleResult::~CSingleResult+0x27
> 0d 0202e0bc 1f35244b msadce!CSingleResult::`scalar deleting
> destructor'+0x8 0e 0202e0e8 1f352518
> msadce!CMultipleResults::mrInitFetch+0xb1
> 0f 0202e11c 1f43fa41 msadce!CMultipleResults::GetResult+0xbd
> 10 0202e15c 1f43f72c msado15!CConnection::Execute+0x13f
> 11 0202e318 1f43f5e6 msado15!_ExecuteAsync+0x16e
> 12 0202e328 1f43f4f9 msado15!ExecuteAsync+0x1f
> 13 0202e3f0 1f43ef4d msado15!CQuery::Execute+0x9fe
> 14 0202e498 1f43a33c msado15!CCommand::_Execute+0x147
> 15 0202e4d8 1f438174 msado15!CXLockContext::~CXLockContext+0x14
> 16 0202e638 1f4448f7 msado15!CRecordset::Open+0x571
> 17 0202e69c 779ffe61 msado15!CRecordset::put_CursorLocation+0x93
> 18 0a96c800 00650073 OLEAUT32!APP_DATA::FreeCachedMem+0x85
> WARNING: Frame IP not in any known module. Following frames may be
> wrong. 19 000008ec 00000000 0x650073
>
>
> As with all multithreading issues, the server runs fine when not under
> stress.
>
> Is there a stable version of this driver available (maybe an older
> version) ?
> Can anybody recommend a commercial driver version ?
>
> thank you,
> Markus.
>
>
>
>
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