Impossible speeds on CalDigit FASTA-4e card

[Elliott Balsley]

I noticed CalDigit claims 450MB/s on their FASTA-4e eSATA card. Since the card is SATA II, I thought this was a typo, so I asked their tech support and got this response:

450+ MBps is not a typo, I will explain to you how we reached that speed. The FASTA 4e card is a SATA II 3G card, but when using a 10 drive solution with our FASTA 4e card we reached 450 MBps. We also tested a 20 drive solution and reached 800 MBps with our FASTA 4e card.

How can anyone get 800MB/s over SATA II? The protocol is theoretically limited to 3Gbps. Assuming zero overhead, that's 375MB/s. They have sent me this card to sample, but I currently don't have access to any fast eSATA storage to test.

 

[Jeff Kilgroe]

If you read the "fine print", it's a composite of all 4 ports. Pretty lame, yes, but some people use the card or others like it to multi-drive arrays in a RAID-0. Just as their response indicates, they're using 10 drive and 20 drive systems, essentially cabinets with multipliers on each SATA input. IMO, it's silly to run a setup like this off such a card and not off a proper RAID host, but whatever...

 

[Elliott Balsley]

I see. That's very clever marketing they have. Although this could be a super cheap way to have a large and fast RAID 0 if a person didn't care about redundancy. Heck, I guess you could even use Disk Utility to do RAID 10 with that many drives.
As a side note, does anyone know what kind of notification OS X gives when part of a software RAID fails?

 

[Tim Jones]

OS X Software RAID Failures

OS X Software RAID Failures

As a side note, does anyone know what kind of notification OS X gives when part of a software RAID fails?

In the case of RAID 0 - "The disk was disconnected improperly" and you're toast.

In the case of RAID-1 - You would see the volume in Disk Manager as "Degraded".

In the case of RAID 10 - The main volume (the RAID 1 part) would be marked as "Degraded" and the failed volume (RAID 0 part) would be marked as "Failed" with the bad drive shown as missing.

Tim

 

[Elliott Balsley]

Thanks Tim. So it's as I suspected: if it fails while Disk Utility is not running and in the foreground, there will be no notification? That sucks.

 

[Tim Jones]

It's all about Number of Spindles versus Channels...

It's all about Number of Spindles versus Channels...

If you read the "fine print", it's a composite of all 4 ports. Pretty lame, yes, but some people use the card or others like it to multi-drive arrays in a RAID-0. Just as their response indicates, they're using 10 drive and 20 drive systems, essentially cabinets with multipliers on each SATA input. IMO, it's silly to run a setup like this off such a card and not off a proper RAID host, but whatever...

Actually, not lame when you consider the cost savings over 6G equipment (SAS II / SATA III). By aggregating the 4 3Gb ports, you effectively provide the potential for 1.2GB/sec (note big B Bytes, not small b bits) using much more cost effective components.

Here's a Blackmagic Test example done using 4, 7200RPM SATA II drives (~105MB/sec each) in the aggregate mode using 4 SAS channels:

Pretty amazing considering the cost, but still not the same as a larger, 6GB-capable system.

If you can afford to go full 6G with a SAS Expander layout, you're still seeing the aggregation of the 4 SAS channels within the SAS expander resulting in a potential sustainable data rate of 2.4GB/sec.

Regardless, the result is fantastic, sustained performance for ingest and editing. You could then copy to raw data to a RAID 5/6 array and/or LTO tape for safer long term storage, but the performance gains versus the cost of an aggregate solution are definitely something worth keeping in mind.

[EDIT] We had numbers for a chassis with a RAID controller built in (so that it only used one SAS channel on the H680). The numbers were a bit less impressive for RAID-0 in the chassis with 8 drives-

Read - 445MB/sec
Write - 423MB/sec

RAID-5:

Read - 442MB/sec
Write - 395MB/sec

Considering that this is a much more expensive chassis and used 8 drives instead of 4, the cost of entry for lower (relative) performance is quite a consideration.

 

[Jeff Kilgroe]

Very true, Tim. I just meant the lame part was the way the card's speed was being presented by their marketing. So, considering the card is EOL and not available anymore except through used channels for the most part -- I actually have one or two of those old FASTA-4ex cards around here somewhere -- I would think we could round up something better for not much [more] money. There are 4 x eSATA 6Gbps cards out there for under $180 and the ATTO H680 is about $365.

 

[Elliott Balsley]

Yes, the H680 seems like a great deal compared to this, with twice as many ports in one slot (through fanouts).
Tim, is that benchmark from the FASTA-4e, or a SAS card?
What kind of enclosure are you using to aggregate the 4 eSATA connections?

 

[Tim Jones]

Yes, the H680 seems like a great deal compared to this, with twice as many ports in one slot (through fanouts).
Tim, is that benchmark from the FASTA-4e, or a SAS card?
What kind of enclosure are you using to aggregate the 4 eSATA connections?

The benchmark is from the ATTO H680 on a Mac Pro 4,1. We test with chassis from many vendors. This one is from a Sans Digital TRX4. I won't mention the RAID chassis vendor name since we're no longer on good terms with them .

 

[Tim Jones]

Very true, Tim. I just meant the lame part was the way the card's speed was being presented by their marketing. So, considering the card is EOL and not available anymore except through used channels for the most part -- I actually have one or two of those old FASTA-4ex cards around here somewhere -- I would think we could round up something better for not much [more] money. There are 4 x eSATA 6Gbps cards out there for under $180 and the ATTO H680 is about $365.

Sort of reminds me of the way the tape vendors talk up the 2:1 capacity and performance. The drives are already big enough and fast enough. There's no need to confuse the users with non-applicable numbers.

One of my favorite 6G eSATA cards is the Sonnet Tempo SATA Pro 6Gb 4-Port. It's under $300 ($231 on Amazon) and works really well for Mac and Windows.

Tim

 

[Tim Jones]

Yes, the H680 seems like a great deal compared to this, with twice as many ports in one slot (through fanouts).

I forgot tom mention, don't mix up "ports" with "channels". The H680 has 2 "ports" and 8 "channels".

Tim

 

[Jeff Franklin]

I have a FASTA-6GU3 that is used by some of our 4-wall clients. LAst time they were here they had two drives connected via the eSATA ports. In another thread on Reduser, Caldigit says the speed drops when two drives are connected. They also said the 4e card would be better. I wasn't sure how the 4e card is different or better.

So to get the fastest connection when two (or more) separate non-RAID drives are connected is this the best card? Or is there a better one?

 

[Elliott Balsley]

What Caldigit told me is the 4e uses a different chip, which is just all-around better (and more expensive). But for just a little more money, you could get the Atto card and have more channels and SATA III.

 

[Jeff Franklin]

Thanks Elliot. The ATTO is overkill for our typical use, so I think I'll try the 4e.