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bobbyFX

Getting The Most Out Of Performance

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I want to play games while encoding video from high quality DV to MPEG 2. Which of the following setups would yield the greatest performance?

A - 2 drives in RAID 0 containing Windows, video encoder, game

1 drive containing DV files and MPEG 2 files

B - 2 drives in RAID 0 containing Windows, game

1 drive containing video files and video encoder

Feel free to suggest any other setups. ALthough I would like to run my operating system on RAID 0 in any case.

Also, if I don't play any game, would the encoding be faster with setup A or B?

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transcoding is a highly CPU/RAM speed bound activity. So, if you set the priority of the encoding to low/idle you should not have a problem even doing these things on a single disk.

If you want the smoothest gameplay, then I'd keep all the video on one drive and the OS/apps on another.

The encoding process might go marginally faster by having the source and output on different drives, but the difference will probably be negligable... as I've said this is not a situation where disk speed makes much difference.

As has already been pointed out in these forums you're best off spending your money on a single fast drive for your OS vs two slower ones in RAID 0. But hey, it's your money.

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BobbyFX,

Blakewry is correct about the irrelevance of the disk drive in transcoding.

The hard drive is also largely irrelevant during the course of gameplay.

In general if you perform multiple disk-related tasks the most efficient setup should be two independent volumes (each containing the data required for one task). This minimizes seeking. However, neither of these tasks are particularly disk limited and disk performance is probably of no concern. To be safe I suggest two seperate volumes.

Also, unless you require MPEG II, say, for compatibility with most DVD players, I would suggest you take a look at Xmpeg and other DivX codecs. Doom9.org is an excellent place to start. Such codecs offer equal quality at lower bit rates (or better quality at equal bit rates :) ).

Do well.

Jonathan Guilbault.

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I tend to agree here, esp. with the dual CPU suggestion, though in the long run a cheap $400 or so system to handle your encoding is probably an even better option. Another option would be a hardware-based MPEG board, though this tends not to be inexpensive.

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I absolutely agree with btb4.

It is much cheaper to simply offload the encoding onto a seperate, cheap system than to go with dual CPUs. In fact this the exact route I intend to take to reduce the burden transcoding places on my primary PC.

I am waiting for a cheap 939-pin A64 and, probably an nForce 250 to build a little headless box. Hopefully a nice Shuttle XPC will appear this summer. Additionally, there are tremendous frames/second/dollar deals on both P4s and Athlon XPs right now (XP-M 2500+, XP 2800+, P4 2.6-2.8).

Of course all this is certainly more than you originally intended of course. I don't think cdx2k1 was serious in his suggestion.

Do well.

Jonathan Guilbault.

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I could use a cheap computer to do all the encoding, but that would take a lot of time and would defeat the purpose of having a fast computer. It's not nice to have to wait 12 hours for a AVI file to be encoded then another 12 hours to author the DVD. Gilbo if you use a slow computer to do the encoding then what do you use your primary computer for?

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G is correct - this is why most encoding farms are many many "decent" systems, instead of a handful of monsters. I'll ignore load sharing etc. for this....

I think you are overestimating the differences in time involved, esp. you plan on multitasking during encoding and thus stealing cycles from the encoder. Consider that Pentium® 4 Processor at 2.66GHz with 533MHz front side bus is a complete system, including a 17" LCD for $599. Mess around a bit and you can do even better for less - for example, lose the LCD, add memory and a GBe NIC, etc. Even if you are using a codec that supports dual CPU usage, and you don't multitask, a dual CPU 3.2G Xeon is not going to do that much better, for the 10X in $ you'll spend. If system "A" takes 12 hours, then system "B" might be 8 or 9 - maybe 5 or 6 at the low end for certain codecs.

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And to clarify - the dual CPU idea is more to permit the mutitask option than for encoding. Expect 10-15% from a dual CPU in encoding without multitasking, depending on the exact codec and the software used.

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bobbyFX,

btb4 has the essence of my point. The chips I suggested are not at all slow. They offer the majority of the encoding performance of a chip like a 3.2Ghz P4 for a fraction of the price. You can get far more frames/second/dollar and you are only giving up about 10-15% in performance. Especially if you are willing to overclock. I don't normally bother overclocking but I would certainly overclock a transcoding box.

The point is that those last 10-15 percentage points require many times the investment in money.

Additionally, it is very simple to send half of the*.vobs to one box and the other half to another. Or half the songs to one box and the others to another. This is another route I am thinking about. There is a huge performance/dollar discrepancy between the low and midrange chips relative to the high end chips. For example you can easily buy several (I think 4 at the moment) XP-M 2500s for the price of a single P4 3.2Ghz.

Regardless, I think this speculation is largely irrelevant to your question. It is a lot more work than simply using your primary system. The only reason I have been thinking of moving in this direction is that I often need as much free CPU on my primary system as I can get, but I also go through large bouts of transcoding frequently.

Hopefully that further clarifies the point btb4 and I were trying to make.

Do well.

Jonathan Guilbault.

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