Mixing HDHRPrime + Ceton ETH ?

[Crash2009]

Missed that one by a mile.......I was totally wrong on that one.

Here is the PRTG report.....

http://www.thegreenbutton.tv/forums/vie ... 311#p22311

13 mbps per HD Stream on a Ceton Infini4.

[McGary]

Agree ... the network bandwidth isn't at all likely to be an issue. I'd be more concerned about whether or not a hard drive can sustain the recording bandwidth if I went to 9 tuners. Assuming 9 HD streams at perhaps 20Mb/s, that's 180Mb = 22.5MB/s that has to be written to a hard drive. That's well below the sustainable write speed for a disk (modern drives can typically do over 100MB/s) ... HOWEVER => it's not a linear stream, so there would be a lot of seeks in between the writes (since there are 9 active files being written).

I'd assume the WMC buffers a lot of this data and the writes are relatively large ... so there shouldn't be any problem sustaining this rate. But it CAN get pretty busy => especially if there's also activity by a user watching something (either a different show or one of those being recorded) and perhaps an extender or two doing the same thing.

I'm just curious if anyone's pushed this to the limits of 9 (or even 12) active tuners. I suspect I'll end up buying one more Prime "just because" and testing with 9 recordings and 2 or 3 "watchers" all at the same time, just to test the limits a bit ... but it'd be nice to know if anyone else has already tried that.

[blueiedgod]

9 HD channels at once

I don't think that's going to work. Each HD recording stream is about 1300 mbps (13% of your gig network). 7 HD recordings (7 X 1300) would put you at 91% of saturation. Your HTPC could play 1 of those streams through its own display system without adding to the network load. The minute somebody turns on an extender or plays a recording, I think you will get some network issues.

My 1300 mbps calculation is based upon testing with PRTG Network Monitor.

http://www.paessler.com/tools

We have 12 tuners (Ceton InfiniTV6 ETH and 3x SiliconDust duals for OTA). Each stream is less than 15 Mbps (theoretical max is 20 Mbps). 12 streams is nothing for a gigabit network.

Even with 5 extenders, which essentially double your throuput for the first 5 tuners, we rarely hit 1/3rd network utilization when all 12 tuners are in use.

[McGary]

12 tuners !! I'm not surprised the Gb network doesn't have a problem with that. Do you record to a RAID-0 array? Or perhaps an SSD?

I'd think the disk activity with 12 streams (plus perhaps 5 active extenders) would be more than a single drive could keep up with.