multiple simultaneous transcoding to multiple MVPs

[MH2006]

Hi Im considering upgrading my dedicated SageTV server to a dual core AMD X2 4200+ (right now its an ancient athlon 2400+). First of all, does sage support multiple simultaneous transcoding of DivX to multiple MVPs? and 2nd would that processor be enough to handle it...and if so how many instances do you think it could handle,2, 3, 4 ? Anyone try this and have some insight. Also, would the dual cores be utililized (if not i mean a single core 3700+ would be better i guess seeing as the X2 above is the equivalent of 2 3500+ one of which would be wasted, thereby saving about 150$) Lastly, can you transcode and placeshift simultaneously.

Thanks.

[Fallen Kell]

I don't know if the dual cores would be used specifically for sage's transcoding, but I will say that it WILL help a LOT for general usage. The big thing here is the fact that the sagetv process thread(s?) (not sure if multi-threaded application) would not be interupted by operating system duties as often, basically meaning more CPU time is spent working on doing what you want sagetv to do and not doing things like networking, disk i/o, memory paging, time based interupts to check things like the date, virus scanning, etc., etc., etc., basically everything else that the computer is running in the background. Just hit ctrl+alt+del on your system to bring up the "Windows Task Manager" and click on the "Performance" tab. Under the totals, you will see a value for "Threads", which are the number of seperate threads that are actively being run on the system. With 1 CPU, the CPU needs to give "processing time" to each and every one of those threads. To do that it has to basically load the instruction set for the process, run the group of instructions, stop running on that process, put new instructions that may have been generated back into the process stack, swap out the instruction set for another process and repeat the process again. All the while, other things might "interupt" the CPU, in fact it happens all the time, heck typing or moving the mouse "interupts" the CPU, and even keeping track of time does as well. When an interupt occurs the CPU stops doing what it is doing and handles the interput immediately because it is a high priority type action... Now, basically what this all means is that if you have a lot of threads, you will get more CPU time for your important applications if you have more CPU's that can run your application, which will in turn mean better performance.

2x 2.2GHz cores will get you more CPU time for a single application on a Windows XP system then 1x 2.7GHz core, simply because there are so many other things that are running along side it. In my case, I have between 422-428 threads running on my system right now, and I only have "open" a web-browser and I am running SageTV in service mode...

[MH2006]

Nod,

I think I would upgrade anyways for the added benefits and stability. Its probably gonna happen (you know how it is when you think about getting something).

I've done some searches, can't find any info on multiple transcoding attempts. I'll report back my results if I go through with my upgrade in any case. Still would like to know what to expect.

[Narflex]

Yes, SageTV does support multiple simultaneosu transcoding to MVPs are Placeshifter clients. That setup should easily be able to handle two. It *might* be able to do three. With the right tweaking you could probably even get it to do four by reducing the quality of the transcoding...but that's not officially supported.

[MH2006]

Cool thanks for the info Narflex

[MH2006]

I actually did setup my Athlon X2 4200+ based SageTV server and would like to report back my findings. It seems each divx transcoding to MVP instance utilizes about 30-45% cpu usage. So thats 2 reliably simultaneously. As for Placeshifting: at about 500Kbps each instance utilizes only about 10% cpu usage, quite a bit lower than divx/ac3 transcoding to MVP. The system could easily handle 5+ i would think (didin't really bother to test it). In any case I would say that such a system could do 2 divx transcodes to MVP, 1 placeshifting instance over internet, and ofcourse numerous regular Lan clients, all at the same time without so much as a hiccup.

Peace

[ybrew]

Ok, dumb newbie question....

I'm pretty sure I understand transcoding, but just to make sure -

This is completely unrelated to TV recording playback from standard def tv, right?

If I want to watch 4 different recorded programs on 4 different MVPs, I shouldn't have problems, right? I'd just need to worry if I was watching Divx programs I ripped or downloaded.

Correct me if I'm wrong.

[Opus4]

Yes, if the files are mpeg2 recordings that the MVP can play using its internal hardware decoder, then no transcoding is needed & very little cpu time on the server will be needed.

- Andy

[ybrew]

cool. That's what I thought.

Thanks!