The mod_perl 2.0.2 + apache v2.2.3

mod_perl 2.0.2 + apache v2.2.3 from
http://www.devside.net/server/webdeveloper

httpd.conf
ThreadsPerChild 1920
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I have a project must upload files to win2003 server. So i do the job by
implement
Protocol (Connection) Handlers in mod_perl. But the server will very busy
when > 5
connections connect to apache at the same time. Maybe one connection upload
big file
(100M) . But in general the files is < 5M. The server have 4 cpu and Ram is
4G.But
sometime the new connection will hang a little time (sometime can not accept
new
connections) .The cpu is not up to 100% and memory usage is still low.I have
some
problem want to know.

1. How the mpm_winnt work? It use one thread to keep the one request?Or it
do many
tasks by generate many thread on one connection?

2.Which one is more effective between Socket-based or Bucket Brigades-based
Protocol?

3.The win32 task-manage show that the apache have 2 process.But sometime it
have >2
process. Why? The apache use thread not process?

4.Have the Apache v2 mpm_prefork on win32? We testing the same code on
linux.The
performance is very very good than it on win2003 especially it have
muti-connections on
httpd.

5.Tuning the win2003 register will erase the upload file time.
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic es\AFD\Parameters]
"DefaultReceiveWindow"=dword:00019000
"DefaultSendWindow"=dword:00019000

Need i up the DefaultReceiveWindow value(>102400) to improve the
performance
?