4K sector drives and RAID cards

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Stereodude

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Has anyone seen any data on what the impact of the newer 4k sector drives is on HW RAID cards? Can they be used as normal? Do they need the jumper set to put them into compatibility mode? Does anything special need to be done to align the partition on the resulting array?

My gut feel is that the RAID cards would need some sort of updated firmware to allow them to align the data on the 4k sector boundaries of the drives (if they don't by default) otherwise there will be a performance hit. I would also assume that the partitions on the array do not need any sort of alignment because it's already been done (or not) by the RAID card.

I'm not in any eminent danger of running out and buying a stack of Samsung HD204UI's, but I'm sure I will end up encountering this problem sooner or later so I'd like to know what I'm in for.
 
ddrueding

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I'm just guessing, but I bet the RAID guys have simply not put 4k drives on the HCL and consider the problem solved for now. I agree that a firmware update would likely be necessary.
 
Handruin

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Unrelated to your specific question, but I looked up that Samsung drive and the detail spec says "4K Sector with Emulation". Are all the drives that use 4K sectors using emulation to achieve this or is there a drive which has a native implementation?

I also wonder if firmware updates would be needed for RAID cards for caching purposes. I don't know how it's done now, but if they base the caching on 512 byte, then jumping to 4K might cause problems if the caching algorithm wasn't designed to read chunks of that size?
 
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I have a similar question as Doug. I'm thinking of ordering this 2 TB Samsung now that Newegg hopefully fixed the packaging issues. Sweet deal at $99.99 shipped with the promotion code. Only possible issue is it's using 4K sectors with 512 byte emulation. Would this cause any performance or compatibility issues with XP 32-bit?
 
ddrueding

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Not once you run the sector alignment app. Were you planning on using it for storage? Imaging an old OS install? New OS install?
 
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Handruin said:
Unrelated to your specific question, but I looked up that Samsung drive and the detail spec says "4K Sector with Emulation". Are all the drives that use 4K sectors using emulation to achieve this or is there a drive which has a native implementation?
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I'm not sure. I saw people bemoaning the fact that the WD 4k drives don't allow a native interface. I'm not sure if that's accurate. I would have expected the jumper to switch between 4k native and 4k with internal 512kb emulation.
I also wonder if firmware updates would be needed for RAID cards for caching purposes. I don't know how it's done now, but if they base the caching on 512 byte, then jumping to 4K might cause problems if the caching algorithm wasn't designed to read chunks of that size?
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I don't think the caching would need the update. I suspect they use much larger chunks. I think the firmware update would be needed so the cards would align their data writes to 4k sectors.
 
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ddrueding said:
I'm just guessing, but I bet the RAID guys have simply not put 4k drives on the HCL and consider the problem solved for now. I agree that a firmware update would likely be necessary.
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I did some more digging after I posted and it seems the guys over at overclocker.net say the 4k sector drives don't play nice with RAID cards even when the 512k compatibility jumpers are set (and of course there's a performance hit) from the lack of alignment by the cards though I didn't see any specific issues mentioned explicitly.

I guess I'll be buying a stack of the Samsung 2TB HD203WI drives before they evaporate from the marketplace since I doubt Dell or LSI is going to add 4k sector support to the Perc 5/i and 6/i RAID cards and I can live without this headache.
 
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ddrueding said:
Not once you run the sector alignment app. Were you planning on using it for storage? Imaging an old OS install? New OS install?
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Just storage. I'm nearly out of space on my 200 GB drive. I'll leave the 200 GB for the boot drive for now. Down the road, maybe next year, I plan to buy an SSD, and will image the old OS install to boot from it.
 
Mercutio

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Knowing how Enterprise hardware is, I sincerely doubt they'll bother to fix any potential issue with 4k clusters for anything short of a new product line. Hobbyists aren't exactly the target market for serious RAID cards, and the people who are the target market probably aren't upgrading their existing arrays to support those drives.
 
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Mercutio said:
Knowing how Enterprise hardware is, I sincerely doubt they'll bother to fix any potential issue with 4k clusters for anything short of a new product line. Hobbyists aren't exactly the target market for serious RAID cards, and the people who are the target market probably aren't upgrading their existing arrays to support those drives.
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I agree... Hence my comment about buying a pile of Samsung 2TB HD203WI drives. :sunny:
 
LunarMist

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Prices are higher than they were a few months ago though.
 
LunarMist

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I picked up two of the the old models at $110 each for safekeeping.
 
LunarMist

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Wow, 10? I'm waiting for 3-4TB drives before buying too many 2TB drives ahead of the need. I only have ~60TB in total drives now.
 
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I don't think we're going to see any SATA drives larger than 2TB (HD203WI) that aren't 4k sector drives. I don't want to have to buy a new RAID card (I've already got a few PERC 5 & 6's), so that means I need the older style 512 sector drives. I certainly don't need the extra space now, but by the time I need it I won't be able to get the drives. I can only use 8 drives in an array, but it's best to have a spare or two.

My backup server is gradually filling up and will be full soon enough. The idea would be to transition the 8 1.5TB drive RAID-6 to the backup server and put an 8 2.0TB drive RAID-6 in the main server.
 
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Well, I purchased the 2TB Samsung I linked to earlier. It turns out Newegg packed it well, and it works fine. I had to update the BIOS in my M/B to keep the system from hanging while it was trying to detect the drive ( see description of the procedure here ).

Also, to partition the drive I used this procedure. I started the partition at sector 64, then used 4K allocation units while formatting. Only issue is my A7N8X-E M/B is SATA 150. The STR is capped at ~108 MB/sec for the first 50% of the drive. Not a big deal actually. This is by far the fastest drive I've had in terms of STR despite the bottleneck.
 
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Mercutio said:
I'm shocked that your A7N8X still works.
Click to expand...
So am I. And surprisingly, I haven't had to replace the caps-yet. In a bit of irony though I came very close to bricking the M/B while flashing the BIOS. We had two tornadoes touch down in NYC on 9/16-one in Brooklyn, the other in Flushing. About a minute or two after I flashed the BIOS, before I even had a chance to restart the system to see if the new BIOS worked, the tornado came through. Power was out until the following afternoon. I only got back my cable service yesterday. When I get a chance I'll put some pics of the neighborhood on Photobucket. Trees and power lines were down everywhere. The local utility did a good job restoring power. The main roads are mostly clear now although some sidestreets are still blocked off.
 
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These 4K drives are causing all sorts of problems with hardware RAID, software RAID, modern filesystems like ZFS & BTRFS, not to mention logical volume management like LVM. I'd avoid them if you want to use them in any role like that.

Until they start honestly reporting their sector size as 4K we're going to keeping having trouble. Windows 7, Vista, Linux, Solaris, etc. are all designed to be able to handle them without emulation.

Unfortunately, they can't report their true sector size until motherboard makers move to EFI or BIOS stops being designed around 20 year old technology.


Stereodude said:
I'm not sure. I saw people bemoaning the fact that the WD 4k drives don't allow a native interface. I'm not sure if that's accurate. I would have expected the jumper to switch between 4k native and 4k with internal 512kb emulation.
Click to expand...

None of the drives that I'm aware of at the moment can have the emulation disabled.

The jumpers are for causing an LBA offset. The drives that have them will offset the LBA 63 partition start to LBA 64. They do this silently. An OS which is 4K sector aware will then be completely fucked up if this is enabled. It's basically a Windows XP mode, and is a terrible hack that has the potential to screw all sorts of sensibly designed things.
 
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Gilbo said:
None of the drives that I'm aware of at the moment can have the emulation disabled.

The jumpers are for causing an LBA offset. The drives that have them will offset the LBA 63 partition start to LBA 64. They do this silently. An OS which is 4K sector aware will then be completely fucked up if this is enabled. It's basically a Windows XP mode, and is a terrible hack that has the potential to screw all sorts of sensibly designed things.
Click to expand...
Thanks for the explanation on the jumper. This only further confirms that I need to get the stack of HD203WI's I had been planning to get.
 
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sechs said:
I'd suggest buying from the eWiz site rather than superbiiz. Inexplicably, I've always received slower yet more reliable service from eWiz.
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Too late... I bought one with the coupon code from Superbiiz yesterday. Ironically I got an e-mail from eWiz indicating the drive shipped today.

Now I just need like 9 more. :idea:
 
LunarMist

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The 2TB F4 is only $95 now, 4KB sectors and all. :spiderman:
 
sechs

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Stereodude said:
Too late... I bought one with the coupon code from Superbiiz yesterday. Ironically I got an e-mail from eWiz indicating the drive shipped today.
Click to expand...
They use the same back-end, but orders are fulfilled differently. They also have different CS.
 
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