save live stream to files, but data is caching in memory

[ericlee26]

Dear all,
First, I am sorry for my poor English.
I have a problem in saving a live stream to files.
I am sure that the live stream is fine and i want to save it to files.
I found that the stream data all is saved in memory, but when I stop vlc,
those stream data is dump in files immediately.
I use VLC with version 0.8.6f.
I have tried some options like "sout-mux-caching=300" and "rtsp-caching=300",
but they do not work.

I really need some help....

best regard.