I've had no problem with Vertex3's as ZIL/L2ARC devices so far.

Peter,

Vertex3's are SATA based SSDs. My question is about PCI-e based SSDs -- different fish completely.

PCI-e SSDs are cards that you put into a motherboard slot. They can have MUCH higher performance numbers than 6 Gbps SAS or SATA drive since they run on the PCI-e bus.

The RevoDrive products are not PCI-e SSDs. They are all based on SATA SSD drives that are bolted to a PCI-e card with a low-cost SATA RAID chip. With possible exception to the "3", the older ones just show up as 2 or 4 individual drives unless you're running Windows. I'm not even sure the "3" will work because it's supposedly a custom controller.

As to the Fusion-IO, no idea, but they claim "Solaris 10 U8/U9 (x64)" works, so you've got a shot at it.

Really wish you could edit on this forum...

Anyway, it looks like the SAS controller on the "3" may be made by Marvell. Early Windows driver versions had multiple hardware vendor IDs, two of which belonged to Marvell. The newest driver release only has an unknown id that I can't find in any DB.

According to Tom's Hardware ([http://www.tomshardware.com/reviews/revodrive-3-x2,2967.html]) the controller is one of the latest SandForce SF-2200.

I do not agree that the PCI-e SSDs have low cost SATA RAID chips. I do agree that the base flash components are the same regardless of SAS/SATA/PCI-e nature of the device. The performance numbers certainly show a whole other level of performance.

P.S. I also have problems with this forum; can't edit, search is just OK...

No, that's the controller of each of the SSDs on the card (there are two on the regular models, 4 on the X2). There is still a SATA or SAS controller that ties them all together. On the "3" it's a Marvell SAS controller, I believe the earlier ones were just fakeraid chips.

You are correct about the SSD controllers.

With respect to the PCI-e to SAS controller, it seems that OCZ has built there own (SuperScale controller) chip and "VCA Architecture" (Page 2 of my link has the details)

It seems that the card presents a single drive to the system.

Sean Leyne wrote:

You are correct about the SSD controllers.

With respect to the PCI-e to SAS controller, it seems that OCZ has built there own (SuperScale controller) chip and "VCA Architecture" (Page 2 of my link has the details)

It seems that the card presents a single drive to the system.

I'm pretty sure they don't have the resources to build their own controller. As I mentioned above, the early drivers for the "3" gave a vendor id that belonged to Marvell, pegging them as the source for the SAS chip. The closest thing Marvell makes is the 88SE9485, and it's possible that it's one of those with half the channels and custom firmware, but even at that, you'd need to work some magic because the vendor and device IDs won't match any existing parts, and OCZ has almost certainly worked it over to provide their VCA tech and to pass TRIM commands through to the individual SATA drives.

Since OCZ has said several times that they do not intend to create drives for the RevoDrive 3 for anything other than Windows, nor will they release any info on the custom chip so that the community could create drivers, you're best off not giving them your business and instead sticking with standard SATA SSDs from Intel (X25-E for ZIL, X25-M G2 or 520 for L2ARC).

Jason,

You may have forgotten that OCZ acquired Indilinx last March. So, they now have the resources to build a controller. Whether they have or not is a separate issue.

My problems with the X25-E is are (1) my HDD chassis has a backplane with SAS expanders [which are contra-indicated with X25-E] and (1) the X25-E has SATA interface not SAS, so an interposer is required.

STEC has just announced some new SLC e-SSDs but their pricing has always been STEEP.

Indilinx makes SATA NAND controllers, not SATA or SAS host bus controllers. The latter are far more complicated and outside the realm of knowledge for both companies. Like I said, it's likely a Marvell part that they had customized to provide more features.

Anyway, if you have a real aversion to using the SATA Intel drives that everyone else uses, and can't/won't pay for a SAS SSD (there are a few companies that make them, STEC, Seagate, OCZ, to name three, they should all be in the $10-12/GB range for MLC flash, about 2-3x that for SLC), then look into the DDRDrive. The founder of the company that makes it posts here on occasion and has committed to driver support for all versions of Nexenta 3.0 and higher. You won't get the raw throughput of SATA/SAS 6Gb SSDs since it runs over PCI-e x1, and I believe it caps out at 4GB capacity, but it will crush just about everything else on IOPS.

A much cheaper option would just be to add an extra HBA so you can skip the interposers and expander; SSDs should really be on their own HBA anyway for maximum throughput. My main storage box at home has all the HDDs on a 9201-16i and the SSDs on a 9211-8i. Depending on the size of your chassis, I've used plastic brackets that let you mount (4) 2.5" drives in two card slots.

http://www.scythe-usa.com/product/acc/064/slotrafter_detail.html

Jason,

It is not that I have an aversion to using the Intel SSDs, in fact I have 2 of them. Nexenta has told me directly, published in their HCL and in postings to various ZFS forums said that X25-E should not be used with SAS expanders.

Its possibly not just the X25-E. For the record, I have had extremely bad experiences using any sata based drives on SAS expanders. Using an LSI Raid card with SAS and SATA drives in a SAS expander (a supermicro machine) simply resulted in zpool crc errors across all drives - particularly the SATA drives. This issue only showed itself under high io loads. Removing any SATA drives rectified the issue.

I ran a 80gb fusion io iodrive on openindiana and that ran very good. I'd like to try it on nexentastor as well, but the installation procedure didn't go as smoothly as on openindiana. When I have some time over I will try again.

Chris Parsons wrote:

Its possibly not just the X25-E. For the record, I have had extremely bad experiences using any sata based drives on SAS expanders. Using an LSI Raid card with SAS and SATA drives in a SAS expander (a supermicro machine) simply resulted in zpool crc errors across all drives - particularly the SATA drives. This issue only showed itself under high io loads. Removing any SATA drives rectified the issue.

Were you using interposers on the SATA drives?