Odd system, sortof...

[Dominique Grenier]

I'd like to get you're input on the system we plan on making. Before considering anything, bear in mind that transcoding time isn't critical for us, right now. Most of our work is into production, our post operations are quite small, so far.

We wanted to make a small system using what we already had on hand and rather use our money to spend on what we could really make money on. Basically, what I'd like to know is if I'm right in identifying the bottlenecks of such a system.

So, what we have on hand is two old G4 and three Macbooks. I know that I can't use the G4's to trancode since they aren't Intel based (obviously), and anyway, they're so slow I wouldn't even bother.

What I'm planning to do is use the G4 466mhz (Digital Audio) as the "data controller", that is, all drives will be connected to this station. I'm going to add a PCI card with three FW800 ports. To this card, will be connected two Sonnet R400Q quad-drives enclosures, filled with 1TB SATAII drives. Obviously, the bottleneck here will be the FW800 interface. But as far as I know, there is no PCI SATAII card, right? I guess this is because it wouldn't even make sense since the speed of this interface wouldn't keep up. My guess here.

Both drives enclosure will be setup as RAID-0, and I'll manually mirror one on the other (rather than make a RAID-1), in order to avoid human error.

The G4 will share this data out via its Gigabit Ethernet, and I'll add a Gigabit Ethernet card as well, in order to setup a link aggregation. This link will be hooked to a Linksys 8-port managed switch (SRW2008), which will in turn be connected to the three Macbook when we have transcoding to do.

Now on the Macbook, according to the tests I made, transcoding 4k 16:9 at half-Res yield approximately 1 fps. So using the three machines should gives us about 3 fps, which is OK for what we do.

I'm wondering what kind of speed impact the G4 will make for feeding the network from the RAID? Obviously the FW800 link will be a handicap, but since the rendering machines aren't that quick, am I right to assume they won't wait for the data to arrive?

At the end of the summer, we plan on purchasing a new Mac Pro, so almost none of this will matter, but until then, I think this system will be good enough. We will also add a LTO tape drive at this time too.

So what you guys are thinking? Am I day dreaming or whatever you say?

Thanks,

 

[Dominique Grenier]

I guess my question might be a bit too much specific.

Basically, all I want to know is if the G4, although not optimal, will be able to feed the network at the full speed of the FW800 line, or will it slow it down further.

Thanks anyway,

 

[Cail Young]

I did a little test the other day with two Mac Pros on a similar line - the important thing is that the G4 has a Gigabit Ethernet card and GigEth switching - that's the bottleneck. The internal IO should be quick enough but only way to tell is to benchmark the system.

 

[Cail Young]

But as far as I know, there is no PCI SATAII card, right? I guess this is because it wouldn't even make sense since the speed of this interface wouldn't keep up. My guess here.

There are PCI eSATA cards, and they will run slightly faster than FW800 will. That said, I don't know if you can get drivers for G4.

 

[Dominique Grenier]

I did a little test the other day with two Mac Pros on a similar line - the important thing is that the G4 has a Gigabit Ethernet card and GigEth switching - that's the bottleneck. The internal IO should be quick enough but only way to tell is to benchmark the system.

Yeah that's what I figured. The G4 already has a Gigabit Ethernet port, and I intend to add another one to link them using the link aggregation protocol, theoretically doing 2 Gigabit Ethernet.

 

[Charles Angus]

Sounds like it could work.

 

[Dominique Grenier]

Anybody knows if usually a 3 FW800 ports PCI card usually mean 1 bus per port, or it is really only one bus for the three of them?

The one I'm interested in is this one made by Lacie, because I can have a good price on it.