New Server thoughts

[paulbeers]

Okay, so the old 766 mhz celeron in an SFF case server is just not cutting it anymore. Now that I have switched to using an MVP with Sage 4.1, whenever I try to record HDTV, it pings the proc at 100% periodically and has made watching live HDTV almost impossible on my client machine. I started to think about what I wanted to do for my next server and I decided I wanted to use a raid card. Probably a simple Raid 0 for now since I am not ripping DVD’s to my hard drives. It would only be used right now for MP3’s and Television (of which only the MP3’s I worry about losing and I can easily back them up onto a couple DVDR’s). I had one worry though….Am I going to push the limits of the PCI bus which if I remember correctly has a maximum thorough put of 133MB/s. I am planning to use 1 Hauppauge PVR 500, 2 Avermedia M150’s, and a fusionlite 5 and the raid card. That would use 4 out of the 5 pci slots on the motherboard I am planning to use. I am leaving the other one for a possible future add of another fusionlite 5. Doing the math, if I were to be recording all at once, I would probably only be using about 5 MB/s (recording mpegs at 2 GB/hr which would be approx .6 MB/s and HDTV at 9 GB/hr which would be aprox 2.5 MB/s) which would still leave me about 128 MB/s for my raid card doing my very basic math. Can anyone verify that I won’t have any bottlenecks with this setup? What if I also throw in a GB Ethernet card (I think this would cause major bottlenecks if I did this).

[jptaz]

Should be fine...even with all the slots in use...

I have stress tested my system with 3 x PVR 250 and 1 x PVR 500 all at MAX MPEG2 (12Mbits/s) while recording HD TV from USB2 VBOX Tuner all at the same time with no issue. This is about 80Mbits/s which is 10MB/s which my 3ware 9500s-12 in RAID 5 has no problem with not does my PCI Bus which is completely full. I normally only record at 3.25GB/HR because of the MediaMVPs inability to really playback much higher than that...and lower does nor look as good on my HD Set.

My only is, which I have another thread on, is stuttering while playing back on the client when a recording starts, which never happens on clients or MVPs. I doubt this is bandwidth related as it doesn't matter how many 1 to 5, or what bit rate the recordings are at. From what I have seen it is some where bug in SageTV since I can playback using other programs without the stutter when recordings start.

John

[paulbeers]

While it is good to know that I won't hit max with 3/4 hd/sdtv cards on my server and a raid card, I am still a little worried about also adding a GB ethernet card. I suppose GB isn't really necessary unless I start streaming several HD streams and at this point I only have 1 hdtv client.

[jptaz]

Well...Look at it this way.

If you are only going to be streaming the recordings to clients (playing back from a client) and not copying the multiple GB files from the server to another machine then you still are not going to be pushing much across the network or PCI Bus. I have not tried playing HD on my 2 clients yet, but figure each client is only pulling at 19Mb/s so say even if you are streaming 4 HD Streams that is still less than 10MB/s across the PC bus. Eevn if for some odd reason DMA can not be used to transfer the data from the RAID to the GB NIC then it doubles to 20MB/s plus the 20MB/s that 2 HD + 5 SD recordings (Again no DMA between the cards and RAID Controller)...Still only at 40 MB/s and even if there is a lot of overhead you just are not going to come close to the Max throughput.

My Numbers could be way off, but I don't thin so.

John