SATA EFD's ?

I dont think it is rumor.  I have read it somewhere also.

Flash drives which use SATA protocol internally is supported on CLARiiON, starting with FLARE Release 30. From an end-user point of view, they can be used in exactly the same way as the flash drives which were released earlier.

Specifically the 100GB EFD is SATA and the 200GB is available as FC or SATA. They are treated the same by the array regardless of protocol. The 100GB SATA EFD is less expensive than the 73GB FC EFD last time I checked.

Thanks!

Richard Anderson

Senior Technology Consultant, EMC, TME

Phone: 206.229.9263

richardj.anderson@emc.com

Hi i have now get some EFD drives, and yes there are SATA SSD drives for Clariion Flare 30 systems

The EFD drives i got is

EMC Part No: 005048998 Stec Zeus Iops SSD Model  Z16IFE3B-200 / 520UC - EMC whitch is a 200Gb FC drive whit

But i cannot find any performance information on the Samsung SATA EFD ohter than it is 3Gb as the other normal SATA drives, this should be the limititation in the SATA protocol and the imposer board there is on these SATA drives (P/N 250-135-903D) = converter between SATA and FC protocol.

These SATA EFD drives has been sold as the FAST CACHE drive pacage to the NS960 Item # FLNSAF04-200 200GB FLASH DRIVE FOR NS FAST CACHE NEW INS.

So now to my question :-)

Is these SATA EFD drives good for use as FAST CACHE, i think the FC EFD are faster, and when the use of FAST CACHE is in so close connection to the very fast normal cache (DRAM), why are these SATA 3GB dives sold as FAST CACHE ? Yes i persume they are cheaper, but in performance manner the FC should be better for this purpose right.

And is it a good idea to seperate these 3Gb SATA EFD's whit the normal SATA drives, as the 3Gb interface on the drive will slow down a 4GB FC backend loop ?

As always in good latin to seperate SATA drives from FC drives, on the BE busses.

I have 42 FC EFD there vas ment for FAST Tiering, but i can use 20 of these FC EFD drives for FAST CACHE instad of the SATA EFD ment for FAST CACHE in the ordre, isent this better whit performance googles on ?

and then put these SATA EFD on BE busses whit my ohter Normal SATA drives, as all of them will bring down the BE to 3Gb

Regards Kenneth Hansen

Kenneth

First question:

Is these SATA EFD drives good for use as FAST CACHE?

     Absolutely. In many respects, these new SSD drives are even better suited for the purpose than the previous version of EFD drives.

Second question:

And is it a good idea to separate these 3Gb SATA EFD's whit the normal SATA drives?

SSD drives CANNOT be mixed in a DEA with SATA drives. and that goes for the old as well as for the new types.

A DAE containing SATA2 spinning drives can contain SATA2 spinning drives only

A DAE containing SSD drives can contain FC drives as well.

A DAE containing FC drives can contain SSD drives as well.

The new generation SSD drive connects to the backend loop via an FC connection @ 4Gbs. (as does the existing SATA 2 drive) so the loop wil be running at full speed, 4Gbs, no matter what drive you connect.

The thing you want to take into consideration, if anything at al, is to separate sequential / large block workloads from random / small block workloads on each back end BUS.

Remember, a SSD drive actually is not a disk drive, but rather a small computer. Thus a lot of the stuff that you learned in the past about storage devices simply does not fit these drives.

So Kenneth.

I happen to know that you have a pretty smart EMC presaels guy assosiated to your account, so why dont you arrange a meating with him, and get things sorted out?

Regards

Lars B Andersen

EMC Danmark

Hi Lars Thanks for you respons to this tread.

There are thing i want to dig deeper into, so yes a meeting was my tought anyway :-)

But why is the SATA EFD's marked as 3Gb if they connect to the the bus in 4Gb, yes internaly they maybee only work in 3Gb, but will this not give waitstates on the back-end loop, if they are mixed whit 4Gb FC drives EFD or Spindels.

I have been told by an EMC instructor on a course, that those imposer cards really only work in 3Gb, and can be a bottlenek, becourse of the protocol translation.

I absolutely know i have a pretty good presales guy :-) but sometimes it's good to have a second opinion !

So anyone ?

Please see the following thread - this question about SATA 3Gb has been covered in some detail:

https://community.emc.com/message/409770#409770

glen

Thanks Kelleg this tread is really good, i learned something  thanks

But i still thinks it's strange EMC marked the SATA drives (EFD or spindle) as 3Gb speed, this confuses people

Kenneth

They probably used the terms in use for SATA:

http://en.wikipedia.org/wiki/Serial_ATA#SATA_1.5_Gbit.2Fs.2C_SATA_3_Gbit.2Fs_and_SATA_6_Gbit.2Fs

glen

"But i still thinks it's strange EMC marked the SATA drives (EFD or spindle) as 3Gb speed, this confuses people"

Full disclosure requires us to indicate the core technology of the drive. Which, as Lars correctly pointed out, is a better performing drive than previous. Anyway, the tecnique of interfacing the 3 Gb SATA devices to the FC back end is well-known, proven and stable -- and we get excellent performance. THese drives give great IOPS and bandwidth. Note our existing SATA II are 3 GB and you can hit the same back-end bandwidth with them as you can with FC drives. The 3 Gb internal speed is not an impediment in a shared bus/loop arrangement.

Thanks David, but what is the factual speed difference between SATA and FC EFD's ?
I was not managed to find technical information on the Samsung SATA EFD's. but i will try to write to Samsung to get the data.

because if the SATA EFD are as good (Performance vise) as FC EFD's, why have FC EFD's ?

I can se that the FC EFD Stec Zeus drives have

Kenneth I do not have the time to get into a long debate encompassing the dozen or so factors that affect EFD peformance in the real world. If you would like the 'proof of the pudding' have your local USPEED guy do some estimates with the Disk Sizer tool (USPEED only tool).

It turns out comparing manufacturers metrics is an exercise in futility as there are many internal architectural differences which affect real-world performance under a range of different conditions.

"And whit a SATA protocol limitation of 300MB/s (Theoretically from Wiki) then the SATA EFD's cannot be as good as the FC EFD's"

Sorry, that is only 1 factor and it RARELY applies to how the drives are used. Trust me, I have no reason to misrepresent the truth. I do not get paid for selling one thing over the other, I am motivated by happy customers.

Why have both? It is an expanding universe of choices and EMC is always at the forrefront.

thank you for your interest - please take up specific sizing questions with a USPEED rep, he/she will get the answers you need to the solutions yuo must build.

For some insight on those architectural issues - which I presented at 2010 EMCWorld, Flash Drive Architecture (attached, since they no longer end up on PLink)

Great Thanks David, this presentation is good, but this gives me anohter question

Does Sata EFD's also have 16 data opertions lanes ?

Will talk whit our local presales guy, about that tool thanks.

Kenneth

HI Kenneth - I don't have a detailed archi doc on the Samsung - they are holding their design closely. But of course lane count is not hte only factor, speed of access is as well. Basically, we know they perform as well or better in some cases than the FC models we use.