Is the speed of Firewire 400 sufficient for, say, 10 instances of VI?

The built-in SATA has a transfer rate of 1.5 Gbit/s, that's almost four times as fast as Firewire 400. The 2.5" Hitachi harddisks are supposed to have a transfer rate of 540 Mbit/s (5400 rpm) or even 629 Mbit/s (7200 rpm), so the 400 Mbit/s of Firewire 400 seem to be a real bottleneck.

So it might be sensible to consider buying a Mac Mini with a built-in 160 GB hard disk, or replacing the existing hard disk by a 160 GB one.

The problem is that for 2.5" hard disks, 160 GB seems to be the maximum available capacity these days -- for 7200 rpm hard disks it's only 100 GB.

pierre, please don't confuse theoretical throughput a _bus_ (or an interface) can have with the datarate the harddisk itself is able to deliver ... there are peak values possible up to 50-60 MB/s (capital B = bytes = 8 bits) if data comes from the harddisk's cache - dont expect more than 25 MB/s sustained and even less for sample streaming (which is in fact a random read process of tiny data packets spread across the whole disk) ... a single FW400 bus is capable to transport data of 2-4 FW-harddrives used for sample streaming without problems.
christian

Thanks for the information that sample streaming occurs at 200 Mb/s at most. So the Firewire bus is not a bottleneck. But what are the specifications that are important for sample streaming? Is it the average seek time? Does it make a difference whether the drive is 5400 or 7200 rpm?

(Btw, I'm very well aware of the difference between the bus throughput and the hard disk transfer rate. That's why I said that the Firewire 400 bus would be a real bottleneck for a hard disk data rate of 540 Mbit/s = 67 MB/s, the maximum data rate according to Hitachi.)

In my experience 2 hard drives per bus is the maximum recommended but yes you can go to four and have it run without problems but not my recommendation. I think for sample streaming fw800 is essential because of the faster seek times which is the main thing that slows sample streaming down (as someone said many small drives across the drive - fw800 helps with this a lot over fw400).

Miklos.

as already pointed out - if they note 540 Mb/s this is the burst from the harddisk cache (manufacturers don't like to elaborate too obviously on such *tiny* details)

speed matters, for rotation and for seek - compare data sheets of a WD raptor (10K rpm, NCQ) to say seagate (7.200 rpm, NCQ), numbers should be about 4,8 vs. 8,5 ms average seektime (which is the most important figure for random access)

and i'd like to add that hitachi had the far highest percentage of returned hardware during the last 2 years .... this has actually been confirmed to be the reason for their massive negative balance lately ...
christian

Sorry yes, obviously the hard drive inside the case is the most important element - I was just thinking of the interface alone.

ehem ... fw400 vs fw800 has nothing to do with seektime of the disk .... just data throughput on the bus.
i've posted *2-4* drives per FWbus because too much depends on the quality of the drives, of course having just 2 you're on the safe side
christian

[:D] posting overlap

So will one of these harddisks that fit nicely under a Mac Mini, e.g. LaCie mini (seek time: "<11 ms") or Micronet Minimate (seek time: "9 ms") be OK (space is an issue for me), or am I better off with a "bigger" one (in terms of space)?

Pierre you know I saw on the internet sombody selling a hard drive that looks like the mac mini exactly and so fits under it like it was made for it, and it has extra usb ports and firewire drive inside. Looks pretty cool if you want it to fit under the mac mini. Otherwise for normal firewire type drives, the big clunky ones or lacie style, just to the side would probably best, not blocking any fan/air vents on either device.

Miklos.

just to have it mentioned ... please make sure the drive has at least some cooling - many devices are not intended to be used for streaming (permanent random access) and are running hot very quickly.
christian

http://eshop.macsales.com/shop/ministack/

That looks like it might be the perfect enclosure for a Mac Mini.

The macmini looking hard drives are cute, but they are generally made by some of the junkier companies on the market.. like Lacie's mini and the newertechnology one. It looks like Newertech has finally put some fans on their case so that may be better.. but honestly I'd go with a more tried and true drive and let looks not be the factor.

I was going to ask if anyone thought it would be good to replace the internal drive rather than get an external drive.. unfortunately Apple's CTO options are just size increases, no 7200 RPM drive is offered as on the laptop. However I noticed an older article from Barefeats that showed FW 3.5" disks to be faster than any 2.5" disk (internal or external). The test is a year old, done on G4 mac mini's, but I think similar results would be achieved on the modern machines.

http://www.barefeats.com/mini01c.html

Anyhow, I know that Jerome has replaced the macMini's drives for reasons of space and power consumption, but if space isn't too much of a concern it's good to know that FW can be better performance. Also that means not doing a possibly warranty voiding procedure to your mac.

What are the problems with the Newertech cases I linked, Steve? I don't have any experience with them, but to me they look perfectly fine.

As far as I'm concerned the only thing that makes any difference - provided the drive isn't overheating - is the bridge board. While I don't know what board they're using, in general I don't think any enclosures are tried and true; they're all made in some factory in Asia, and distributors can order them with nameplates or without. You can buy drives from a VAR like Glyph with some confidence in their service, but for example I've read several failure reports about LaCie drives on this site. There's not much in a name, in other words, despite claims to the contrary.

I personally would buy that Newertech FW box, stick a drive in it, and plug it in the Mac Mini's port without looking back. The reason I like it is that it has USB and FW ports on it, and that would be convenient.

As to the Mac Mini, I personally wouldn't replace the system drive with a faster one. My hunch is that Apple isn't using those drives to save money, they're using them because the box is small and bigger drives get too hot. But even if I were to replace it, I still wouldn't put samples on the system drive. FW is fine for that.

I also have to confess to having a bee in my bonnet about sites like Barefeats.com. The reason is that they give people just enough information to be dangerous. Most of the specs are completely irrelevant for what we're doing, yet they have a nice ring to them that makes people think they're really intelligent when they quote them (and I'm not saying that about you, just in general). "Dude! My RAM socket is crruising along at 15 whetstones! That's *totally* xTreme!"

OWC has good, tried and proven drive enclosures that are used by a lot of audio professionals. So does Granite Digital - which are a little more expensive and a little more heavy duty. If you want good drive enclosures with good FW chips (oxford 911) drives from either company is a good way to go. As Steve said, you can get a lot of junky enclosures that might look cool but aren't the best for digital audio use.

I have 8 OWC mercury elite drives that I have been seriously abusing for years (some of them I bought in 2002) that have never given me a problem. I finally burned out two drives recently from the 2002 models, but I just plopped in 2 fresh drives and they're good as new.

And unless you don't mind the added expense, I would stay away from Glyph (which I also happen to own a rack mount SCSI drive set up) which I find to be the drive version of Monster Cable - way over hyped and overpriced.

My OWC Mercury Elite failed after 8 months of very modest use so there you have it.

Mm. Well, I have a FW enclosure from Granite Digital (made by Relax) that is, as they say in France, strictement pour les oiseaux.

It was expensive too, from the early days of FireWire. The sucker has never worked all that well, its shoddy plastic trays don't seat well and have since warped, and they want more than the price of a good new enclusure to replace the bridge board with one that sees drives over 160MB or whatever it is. Plus its light was connected by wire the same gauge as a hair, routed in the way when you install drives. Of course that broke long ago.

This is what we call a POS in the art world.

@Nick Batzdorf said:

As to the Mac Mini, I personally wouldn't replace the system drive with a faster one. My hunch is that Apple isn't using those drives to save money, they're using them because the box is small and bigger drives get too hot. But even if I were to replace it, I still wouldn't put samples on the system drive. FW is fine for that.

The Mac Mini's is the computer on which Apple makes the less money. I would not be surprised at all if they only used the components with the best features/price ratio.

The box is small, but in terms of components and airflow, it is not that different from an Apple laptop. The Powerbook has been featuring a BTO 7200rpm drive for quite some time now.

Besides, 7200 rpm drives are not necessarily hotter. In fact, Hitachi's 5400 and 7200rpm drives produce roughly as much heat. I've also read that Seagate 7200rpm drives can actually be cooler than some 5400rpm drives.

My experience is that there is a very little heat difference - they run at roughly the same temperature. They do heat up a bit more when continually accessed (which only happens for big file transfers, and is thus rather rare) but that's about it.

Jerome

@dpcon said:

My OWC Mercury Elite failed after 8 months of very modest use so there you have it.

Well some drives do fail no matter what - most of the time it's just becuase you had the bad luck of the draw. Besides, OWC doesn't make the drives, they get the drives from Seagate, WD etc.

I had two drives die on me that were both under 24 hours of use old. One was in a Mercury Elite case (no fault of the case - I bought the drive new and installed it)

I was told by a guy that worked for IBM in their drive divsion that when they manufacture drives they expect about a 10% premature failure rate. That's right 10%. But they try to catch most of that 10% by doing a burn in period. Most drives that will fail do so within the first 50 hours of use. But some still get through and die long before they should. Generally, if your drive makes it through the first 50 hours, it should go the full lifespan with proper care. That's why I never embark on recording a major session or album onto a brand new drive until it's got at least 50 hours under it's belt. I learned that one the hard way.

Heat is also a major drive killer. Keeping drives in tight quarters without good ventilation will shorten the life of any drive.

Given that you don't happen to land one of the 10%, I've found that the OWC cases are a good way to go.

@Nick Batzdorf said:

Mm. Well, I have a FW enclosure from Granite Digital (made by Relax) that is, as they say in France, strictement pour les oiseaux.

It was expensive too, from the early days of FireWire. The sucker has never worked all that well, its shoddy plastic trays don't seat well and have since warped, and they want more than the price of a good new enclusure to replace the bridge board with one that sees drives over 160MB or whatever it is. Plus its light was connected by wire the same gauge as a hair, routed in the way when you install drives. Of course that broke long ago.

This is what we call a POS in the art world.

I never bought the granite because of the higher price, but I also know that a lot of the early firewire cases don't work as well as the newer ones. Some of my older cases won't take a drive bigger than 120gigs. And I had a few early cases bought from MacMall and other places that were down right useless. The bridges were so bad that just getting the drives to mount half of the time was a battle. I ended up chucking a few cases early on.