This is going to be long i guess
I have worked on XBMC for a week now to get it flawless, i got it worked quite fast with some basic setup, XBMC on my laptop with Wifi to a WNDR3700 router.
But then i wanted to get my home built NAS with the goodies on to stream it to my laptop, i used SAMBA to share a folder, it worked i checked Iptraf and it was around 8-16Mbit/s depending on the movie.
After that i wanted it to go further, I wanted to have the opportunity to take with me my laptop to my friend or parents and then stream the material.
I know this would be possible theoretically because their DSL line is around 16Mbit/s+. So i started to test out with VPN and OpenVPN was the best one to do so i installed it on my NAS and borrowed my neighbors Wifi to test it out, and it worked. So i needed more bandwith i tested my laptop at my job
and it worked flawless, and i checked iptraf the same speed as home.
Could be because my home and job is in the same city and same ISP.
Anyway, so far i got XBMC, OpenVPN, SABNzbd, Sickbeard, CouchPotato, rTorrent, XBMC, website to work that i wanted.
Now i wanted to test it live at my parents, took with me my laptop and plugged it in, OpenVPN worked, XBMC worked with SAMBA and i could start to play a movie. Then the Buffering came i was like WTF!.
Checked the Iptraf at the VPN on my NAS, 3-8Mbit/s.. hmm something isnt right, started to check OpenVPN optimization, did what i could, i checked
my SAMBA configuration all over again, and XBMC configuration.
Nothing worked so i thought maybe the line wasn't enough so i went to my friend, the same issue their. So i started a transfer a file with SAMBA the speed was 1.8MB/s (around 18Mbit/s) the same goes with FTP transfer.
So i thought why is a normal transfer so fast but not the stream ?
So i checked for another solution, FTP, UPnP, NFS. FTP didnt worked as i wanted, UPnP didnt play Rar archives for some reason with Mediatomb.
NFS didn't work with Windows 7, it didn't mater what configuration i did on my NAS, i could mount the folder in Windows 7 but but as fast i wanted to go into it, explorer.exe hangs.. Well so i got back to check even more configurations, didn't find anything.
So yesterday night i was desperate so i took an computer i had at my parents installed Ubuntu 10.10, with OpenVPN and XBMC and mounted my folder with NFS, seriously mount with NFS in Ubuntu was easier then mounting a hard drive...
Well when i got the setup ready it was 5:am on the morning so i had to sleep some, but i did some test first and got the streaming working and now i saw really good speeds on my connection around 12-16Mbit/s was the streaming on through the VPN so i was happy and went to bed.
Now i thought i was done and mounted the NFS drives and updated the library and everything, and was about to test it more then 2 minutes, so I took a 720p movie and started it. It was good for about 10-15min the it started to buffer, i was like whats wrong now ?
Iptraf showed good speeds but then I looked in "top" to see how much the CPU is working and it was on 20-22% idle and 90-100 load and that wasn't so good because the VPN need some CPU power as well.
So i ran into BIOS overclocked my CPU from 2.0Ghz to 2.8Ghz and raise the memory to the GPU, and now the cpu runs around 50-60% with a 720p movie on, and i haven't seen any buffer at all so far.
So what i have learned so far is that SAMBA sucks donkey ass for streaming, to weak cpu/gpu may do some buffering.
Sorry if I have wrote something unclear, it can explain it better if anyone want to, i have found so many guides and how-to
on the NET so i want to share my thoughts a little