I'm experiencing some problems with uploading large files on my installation of WebWiz Forums 9. I need to be able to upload files larger than 2MB, so I've done the necessary changes in the IIS metabase to accomodate this.
Everything seems to be working just fine for smaller files (up to 2-3 MBs), but when I upload a file larger than that the application worker process (w3wp.exe) starts using massive amounts of CPU time. For a 8MB file, the upload process takes about 3 minutes, and most of this time is spent in kernel mode.
I've tried using debug diag on the process, and I've identified the thread that's causing my problems:
Thread 9 - System ID 2924
Entry point msvcrt!_endthreadex+2f
Create time 08.07.2008 13:21:27
Time spent in user mode 0 Days 00:00:02.437
Time spent in kernel mode 0 Days 00:02:47.875
Function Source
ntdll!KiFastSystemCallRet
ntdll!NtWaitForMultipleObjects+c
kernel32!WaitForMultipleObjectsEx+11a
user32!RealMsgWaitForMultipleObjectsEx+141
user32!MsgWaitForMultipleObjects+1f
comsvcs!CSTAThread::WorkerLoop+1f9
msvcrt!_endthreadex+a3
kernel32!BaseThreadStart+34
Unfortunately I'm not all that experienced in debugging processes, so this doesn't really tell me all that much.
I'm running the forum software on a 2003 SE Server w/SP2. I've tried
using both Persits and Dundas upload components, but the result is
exactly the same.
Has anybody experienced similar problems? Any help would be greatly appreciated