I'm planning of buying the following for my storage solutions.

CineRaid Model T04

Areca 1221x Raid controller card

4 Seagate 500 GB SATA hard drives.

I would thank for any Suggestions.

I have MC 3.0 on MAC Pro 3.2 , 2008 model with 4 Gig of ram and Nvidia 8800 GT.

Any Idea?

Thanks. Fred

Are there drivers for the mac with the acera card? Otherwise it looks fine albeit a little expensive maybe. There is a lot on external raid found in this thread.

http://community.avid.com/forums/t/58279.aspx?PageIndex=1

And here is some technical info if you need it

With the advent of HD and the availability of cheap large quantity harddrives many post like these surfaced on the forum. I don't know if it will answer any of the questions you still have, but here's a small lexicon on the subject based on the information i found so far, since in the dizzying world of storage the tech terms overwhelmed me at first.

One note in advance, please note the difference between Mb/s, which is Megabit per second and MB/s, which stands for Megabyte per second. As each byte consists of 8 bits, there is quite a difference. Mb/s is usually used to describe the bandwith a video stream needs, MB/s is used to describe the throughput a harddisk is able to provide. However, both firewire and USB use Mb/s to describe the maximum throughput these protocols are able to handle (yes by all means lets keep it simple shall we?) Hope it helps you a little.

(p)ata paralel advanced technology attachment, the cheap old interface to connect a harddrive directly to the motherbord, allowed transfer speeds up to 133 MB/s

sata serial advanced technology attachment, the successor of pata, and comes in two (compatable) flavours, sata1, which soon was succeeded with sata2. Sata 1 allows transfers speed up to 150 MB/s, Sata 2 up to 300 MB/s. Sata offers faster transfer speeds then either firewire or usb, as the fastest of those, firewire 800 (Mb/s) only allows transferspeeds up to 100 MB/s

e-sata external serial advanced technology attachment, same as sata really, to connect a harddisk to the computer externally. It has a slightly different shaped connector though, which is better suited to the rigours of life outside the computer case. The downside is that its not as easially recognized by the operating systems we use today, and needs specific software drivers... This will no doubt change with the advent of newer OS's. Also note that this connection is purely build for harddisks, and other drive based equipment, such as dvd/blueray burners an their ilk. it is not as versitile as either firewire or usb.

Ok so much for the transfer protocols. Of course there is also scsi and serial attached scsi, but we were looking for cheap storage, and scsi and sas are anything but. All these transferspeeds are theoretical of course, because no single drive we can afford will ever reach those transfer speeds. Most modern sata drives top out at 70 MB/s, this speed rapidly decreasing as the drive fills with files to a meager 30 MB/s. Hence the nifty nerds in devellopement came up with harddisk raid...

raid Redundant Array of Independent/Inexpensive Disks or in short a way to up the transfer speeds a harddisk can deliver, by throwing a few disks together so the computer thinks its one drive instead of many. That way speeds add up, how much they add up depends on the type of raid and the number of drives

raid0 the simplest, cheapest, fastest and most dangerous raid. If the computer says write, all disks write, the same goes for read. However, if one disk in such raid fails, all files are lost. So calling this one redundant is stretching it a bit to be honest, as a drive will always fail according to Murphy's laws.

raid1 not a way to go faster really, only there to deal with the mishap of drive failure. In effect it mirrors the read write actions on one drive to the other. if one of both drives fail, replace it and the raid will rebuild, copying all info on the remaining drive to the new one. Very redundant, not a way to achive faster transfer speeds.

raid 2 to 4 other ways of raiding disks, by now redundant and replaced by raid 5 and 10. Note that for raidsystems other then 0 and 1, you will need more then two disks to let them work, the more the better.

raid 1+0, or raid 10 for short. Just adding the two explained above, having best of both worlds, highest speed and no panic (well a little maybe) if a drive fails. However you need 4 drives to pull this one off though, each pair running in raid 0 and then mirrored, cutting the available space of the four drives in half. (or the other way around of course)

raid 5 ok this is a tricky one to explain. Say you have 3 disks, A, B and C in raid 5, disk A and disk B work as raid 0, adding their speed as data goes to and from them. However, each time a zero or a one is written to these drives, a calculation (A+B=C) is made and the result of that calculation is written on drive C. If drive A fails and is replaced, the raid set is rebuild by reversing the calculation (C-B=A). If C, aka the parity drive, fails, the calculation is just repeated (A+B=C). This sounds perfect of course, allowing you much more diskspace then raid 10 with the same redundancy, but it comes at a price. Because of the calculation you have to make, it will never be as fast as raid 0, and while rebuilding, the speed of the raid drops significantly. This is where the difference between hardware and software raid will show. Also this type of raid will profit in speed mostly if the number of attached drives is increased. 4 is good, 8 is way better, 16 is king (and way out of our league if we look for cheap). 

Right now there are many different raid cards available, running on several types of connections (PCI, PCI-X, or PCI-express) or even incorporated in the motherboard. The main difference between the cheap and the expensive ones is if they allow hardware or software based raids

Software based raid The raid card takes care of connecting the cables, but all calculations to sustain the raid are handed to the CPU of the computer, slowing it down significantly if you use raid 5. This type of raid can also be found in most operating systems of today, when you connect drives to the motherboard.

Hardware based raid Besides the connections for disks, the raid card contains a specially designed chip for raid calculations, doing it much faster then the cpu is able to do, and not burdening it with raid work. Of course the downside is that they are more expensive.

Then there is cables and port multipliers and boy did the marketing people put a spin on this one. If they promise to send several layers of uncompressed HD over one little cable, they are lying through their teeth afaik. (small addition here, there is one cable capable of this, and thats the one that extends the pci-e slot outside the computer, like the new line-up of avid hardware does)

USB 2.0 A widespread way to connect pheripal devices to your PC. Printers, scanners, keyboards, mice, tablets, external drives, hell, even monitors I heard. And all this at the theoretical speed of 480 Mb/s, or 60 MB/s. It's cheap and certainly versatile.... so here is the but: Most motherboards nowadays have 8 to 12 ports available. However its hard to see on the outside of the case if each USB slot is on a seperate port, or if they share one. And there lies the problem. As soon as a USB port has to share a device with another (for example by using a hub) it plays king Solomon and gives each device half the available bandwith. No matter if its a keyboard which uses next to nothing together with a harddisk, both get 30 MB/s. Add another to the hub and it goes to quarts. So take care on which usb slot you connect your drive...

Firewire 400/800 The apple version of USB, though to be honest its older then USB and better. Alas its also more expensive for manufactures to use cause of license fee's and the controller chip which it uses. However this controller chip does take care of the fact that adding more devices to one port doesn't halve the bandwith. Its available bandwith is distributed according to the need of the connected devices. And its capable of sustained high datarates, which makes it the connection of choice for most home video camera manufacturers. (with the added bonus that most people only uses it for that purpose, so no device conflicts to take care of through customers services) The 400 and 800 stand for the theoretical max bandwith in Mb/s, so that is 50 MB/s or 100 MB/s respectively. A word on theoretical here. Those speeds are never reached under normal circumstances, much like you will never drive to the avarage use of 1:20 in your car as it states in the folder. These numbers take not in account the fact that your computer may be doing something else (editing anyone?) besides taking care of the connection with the pheripal device.

e-sata cable the 'rugged' version of the sata cable. Note that the maximum data transfer through such cable never exceeds the maximum the sata protocol allows you.

port multipliers a way to connect up to four drives with one sata cable. This has nothing to do with raid. It's just a way to connect more drives to the computer with less cable clutter. Also note that it doesn't increase speed in any way... chances are the cable becomes the limiting part in transfer speeds, as the max throughput will be 300 MB/s at best.

multilane cable If you want less cable clutter, go for this one. its 4 sata cables banded together in a single wire, with a really rugged connection on each end. High quality comes at a higher price of course...

Well, I’ve got disks covered, the cables… now how to connect all this to your motherboard/cpu? Of course this can be done in various ways and by various slots on your motherboard. Some motherboards offer a raid setup including the raid chip, for others you can use a card containing the needed chips in roughly three types of slots found today

PCI slot, or the Peripheral Component Interconnect, the oldest one of the lot, running often at 32 bits in various voltages and versions Mostly used for audio and firewire cards to use with avid dna products. And boy is this thing limited and slow. The limits consist of the fact that no matter how many there are in your PC, they all connect to the same entry of the CPU, aka bus. Having 2 CPU’s allows you a little more headroom, cause you then you have 2 busses available but you’ll have to go through the motherboard manual to find out which slot belongs to which CPU. The fact that its slow is part of the reason AVID dna hardware wants the bus to the CPU for itself. The peak bandwith being a meagre 133 MB/s shows you why adreanaline never was able to pump out many streams of high resolution video. This limit wasn’t only felt by us editors which led to the:

PCI-X slot, or the Peripheral Component Interconnect Extended (trust me on this, besides being a mouthful, the X standing for eXtended caused loads of confusion… I’ll get to that). This thing is usually found in workstations, running 64 bit, in various versions, voltages, 100 and 133 Mhz etc. the fastest able to bring you a bandwith of 1064 MB/s…. now we are talking. Of course it has the same limitation as the normal PCI variant: plug a raid card in it, and make sure not of the other slots connecting to the same bus are filled if you want/need that speed. It is expensive to build, cumbersome, so again the engineers went to the drawing board and came with its successor, the:

PCI-e slot, aka the PCI-express, or Peripheral Component Interconnect Express, its name causing a wave of confusion much like the MB/s and Mb/s thingy. Now this is a total new design and in no way compatable with the previous versions of PCI. It doesn’t use busses, it uses ‘lanes’, the serial approach. Depending on your motherboard you have a limited number of those lanes, it can be 20 to 48. Each lane allows a transfer of 250 MB/s. There are a number of different slots with PCI-e on each motherboard:

x1 which means that slot is connected to 1 lane allowing 250 MB/s bandwith.

x4 which means this slot is connected to 4 lanes allowing 1000 MB/s bandwith

x8 and x16, the last one allowing a whopping 4000 MB/s bandwith, and this is the one usually fitted with the videocard of the system. x4 and x8 are those used for the raidcards, and for avids new DNxHD hardware. So you see the number of lanes your motherboard/computer has available will be the new number to look at.

As said below in this thread, the actual size of a PCI-e slot does not say anything about the number of lanes available. Especially 8x and 16x slots often have the same size, as at many boards you either get one slot doing 16x and one disconnected, or both the slots doing 8x.

Ok if you came this far you are officially a nerd/techhead. The missus returned home, and she wants dinner… promised to do the cooking today, will continue laterz.

And back again. Now all this bandwith is great, but what do we actually need, and what is available? Well, first to our needs. HD material is the most demanding, and the way of the future, so following the info on the Avid website concerning HD streams, found here http://www.avid.com/dnxhd/features.asp 

Where in order of appearance per stream of video without counting audio:

145 Mb/s = 18.1 MB/s for DNxHD145

100 Mb/s = 12.5 MB/s for DVCPro HD

135 Mb/s = 16.9 MB/s for HDCAM

220 Mb/s = 27.5 MB/s for DNxHD220

440 Mb/s = 55 MB/s for HDCAM SR

For more info on video/audio formats and their datarates, you can use the aja datarate calculator, found here http://www.aja.com/html/support_kona2_swd.html

As it is, most modern harddrives can play such a stream without the help of raid. However we aren't viewers satisfied with one stream, we are editors needing at least four video layers and multiple audio layers. So better multiply those number by 4 and add some overhead for audio, which will give you these rough numbers. 

100 MB/s for DNxHD145

70 MB/s for DVCPro HD

80 MB/s for HDCAM

120 MB/s for DNxHD220

240 MB/s for HDCAM SR

Now we are in the league of raided drives. And searching the internet for their capabilities you will find that most will reach those speeds.... BUT there is the marketing spin again. To pump up the abilities of various raid controllers several techniques are used:

Only mentioning burst speed: the speed with which a harddrive can transfer data for a short amount of time. Which is of no use for us editors, as we need those speeds for hours on end, playing streams while editing. Hence the speed you should be looking for is Sustained Speed.

Empty drive speed: The harddisk is at its fastest and most responsive when empty. Not only because the number of files are small, but also the harddisk starts writing them at the part where it is the fastest. (near the physical center of the disk) The more data fills the disk, the slower it will get in retrieving that data, due to the number of files and indexing involved, and because its written on the slower part of the disk (near the rim). How much slower depends on the disk involved, but its a good reason not to fill your drive to the hilt, and leave the slowest 10% of your disk empty.

Mentioning the speed the raid would be able to deliver if it werent using usb/firewire/multiport cabling. See above for the different speeds the connections are capable of. You can have the fastest raidsystem in the world, but if the connection to your pc isnt up to spec it'll still be too slow.

Another thing to take into account when formatting your drives is the block size. If you use the disk for a lot of small files, like the operating system of the avid software, smaller block sizes are better. If you use it for media, ie large files, take the largest block size available.

Ok time for breakfast... if anything needs to be added/changed keep me posted, and i will

rinzeschuurman, 

Thank you so much for the info. The answer is <<Yes>> they do have a driver for Mac, as well as new firmware posted on 08-18-2008 on Areca website.

I already have this storage configured and running, and I'm really impressed with the performance.

10 bit uncompressed HD, no problem at all.

Fred     

 I know the performance of the acera's is king, got them myself...

Glad the information helped you out... for some its a little too deep into the tech

rinzeschuurman:

Glad the information helped you out... for some its a little too deep into the tech

Hi Rinze,

A little too deep maybe, but still good information.  Thanks for taking the time to post it.

adios,
Carl

rinzeschuurman,

Rinze, that was a great, clear, and easy-to-read summary.  This should be made a sticky for those with disc issues.

The one thing that's missing is the fact that some mobos with dual x16 PCI-e slots share lanes across the pair, so that you get 1 x16 but effectively 2 x8 slots.  This may not be an issue so much now, but it certainly was with early implementations.

 Added it to your satisfaction i hope. Thanks for the suggestion

rinzeschuurman:

Added it to your satisfaction i hope.

Added it and then some!  I'm bookmarking this thread.  Next time someone has a disc speed question - BAM!

 ;) thanks.... and then i noticed i never mentioned usb or firewire..... sigh

Why is this in the PC forum again? 

BLKDOG:

Why is this in the PC forum again? 

 O, so this one is for you PC system then?

These are my system specifications. 

MAC Pro 3.2 GHZ 2008 model, 4 Gig of ram, Nvidia 8800 GT video card. 500 Gig system drive, 320 gig extra drive. Second workstation, Dual Xeon 3.0, Supermicro X6DAE-G2 MB, PNY Quadro FX 1500 PCIe video card. 4 GIG ram. Two Seagate 200 GIG set as Raid 0 for video drive, Seagate 160 GIG ATA 100 7200 RPM sestem drive, Seagate 160 GIG ATA 100 7200 RPM storage. ADS Pyro 64 FW card on slot 1. Lian LI case model V-1200 Server case, High Point raid controller card model 2224, and 550 watts power supply. CineRaid 2 TB with the Areca 1221x storage

Fred