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The Seagate 3TB drive - the real thing

These drives are going to hit the market when manufacturers can drop Windows XP support in 2014. You're going to get a Rev. A quad-core Mac Pro for the price of a hard drive by then. The old 24" Intel iMac for $100-150. PPC Macs are going to be even more outdated then today. May these drives work or not. Until then, you're bound to 2.1TB unless you connect your hard drives externally and use GPT.

The next limit we're going to hit is ATA's 48Bit LBA limit of 127 Petabyte in about 30 years if we keep increasing the storage space by 44% a year. 4K sectors add just 5 more years to that. GPT's limit will get hit in 2070 with 512K sectors, 2075 with 4K sectors, 2077 with 8K sectors, 2079 with 16K sectors and so on. 128Bit LBA blasts that well beyond our grand-grand-grand-childrens lifetime (There doesn't even exist a proper SI prefix for that, 140737488355328 Yottabyte with 512K sectors. 140 undecillion Bytes, or 140 trillion Yottabyte. Terayottabyte or whatever you want to call it).

Be prepared for your first 1PT hard drive in 2026 :)
 
Companies can downgrade to XP until 2020 now.

WD doesn't need to wait. They can just provide a jumper.

Why would they risk losing customers with the new format if they were not going to fully transition soon?

The pace of density growth may slow down in the near future.
 
OK, so the 2.1TB limit has nothing to do with LBA but with the 32-bit addressing of APM and MBR?

So if you formatted the APM disk with 'pdisk E' you could just use upto 256TB today?

And for MBR with 'fdisk -b' ?
 
Have a look at the second image in the first post. What is it? Right, an external drive you can hook up without any problems to you G3, G4 or G5 Power Mac. You just can't boot them.

And yes, you can format it with fdisk -b in Linux, with a drive which doesn't use 512 Byte emulation, which you won't find, but both 32 and 64Bit Linux can boot from GPT on BIOS machines anyways, Windows only can with it's 64Bit variants on EFI. If you do it in OSX, 7/8 of your data gets lost because of the emulation and the manner the driver handles the disk. pdisk does not ask you for the Blocksize, it's provided by the driver (Have a look at the date). To have a fancy car analogy, your car runs fine on regular gas and premium. They introduce a 85% ethanol/gasoline mixture, your 2006 car stutters and doesn't reach it's full speed. In theory, every car engine runs fine on that, just change the ECU software to inject 35% more fuel. Same for hard drives with block larger then 512 Byte. They would run fine, but nobody thought fife years ago that there will be ATA hard drives that have other then 512 Byte sector size, so they just didn't implemented it in the driver because there was no need for it. The block size is stored in the driver description record on APT disks. It's human laziness rather then a technical limitation.

32Bit LBA means it can address 4294967296 (= 2³² = 32Bit) unique sectors, that's 11111111111111111111111111111111 in binary or it's bit representation. If you multiply that with 512 Byte for each sector, you get 2.1TB. If you increase the sector size by eight times to 4K, you alter the the limit by eight times, so it's 16TB for 4K drives - as always, in theory.

When the drives hit the streets in a couple of years, try it. If it doesn't work get an external enclosure. Put a 2TB VelocityRaptor inside your Mac and you're fine. No biggie.

I found the actual code the the XNU kernel.

Code: 
disksize = (u_int64_t)blkcnt * (u_int64_t)512;

See, it's hard coded and doesn't care what the actual block size is. Have a look at the ATA drivers as well.

Oh, and SSDs grow more then 44% a year at the moment, and they're forced to the same limitations hard drives are until they come up with something new. Intel is most likely to apply it's "Tik-Tok" practice to their SSDs as well, so let's just for fun assume that this goes on for the next couple of years, like you're assuming you get your hands on a non-emulating 4K SATA drive while using a Power Mac rather then spend $500 to get a 2006 Mac Pro without any limitations before these drives hit the market.

Steve Wozniak said:
It's just not right that so many things don't work when they should. I don't think that will change for a long time.
Click to expand...
 
Macs have 48-bit LBA firmware since June 2002. And even machines older than that can have non-boot partitions beyond 128GiB with the appropriate driver.

A firmware, OS, and CPU do not need to be 64-bit to fully support 48-bit LBA. Like you can have 64-bit offsets into a file with 32-bit OSes. They are not pointers.

When you run pdisk, if you enter the E command, it asks for the block size.
 
cube said:
Macs have 48-bit LBA firmware since June 2002.
Click to expand...
You can upgrade everything to use 256Bit LBA, as long as you use APM, this is your bottleneck, because it uses 32Bit numbers in it's descriptions, and as long as you don't come up with APM 2.0 which uses 64Bit LBA to refer the to the hard drive sectors, this won't change. Linux is aware of 48Bit LBA since 2002, too, but you couldn't use ATA hard drives with sector sizes other then 512 Byte until 2009.

cube said:
MAXIOSIZE in pdisk is 2048, so that should limit APM to 8TB.
...
When you run pdisk, if you enter the E command, it asks for the block size.
...
And even machines older than that can have non-boot partitions beyond 128GiB with the appropriate driver.
Click to expand...
About the appropriate driver, you may have to find/develop that too for drives which use sector sizes other then 512 Bytes, regardless of what's the maximum block size of pdisk or even dd. Every single piece in the chain can be the bottleneck, may it be 32Bit LBA, which was ruled out for everything other then APM, or 512 Byte sectors, which may be ruled out for everything other then the driver which actually accesses the hardware of the drive.

cube said:
A firmware, OS, and CPU do not need to be 64-bit to fully support 48-bit LBA. Like you can have 64-bit offsets into a file with 32-bit OSes. They are not pointers.
Click to expand...
PATA hard drives had 28Bit LBA, then they increased it to 48Bit. Your PC however natively operates on 32Bit (or 64Bit) but has datatypes for 8, 16, 32 and 64Bit, your APM uses 32Bit, it was sufficient to store the 28Bit LBA of the hard drive. When a software states to be 48Bit aware, it uses 64Bit integers internally to handle that. However APM is not 48Bit aware, but it can address more then the initial 28Bit of ATA, so you run into the 2.1TB limit first, before running into the 127PB limit of ATA, after that, you run into the 8 Zettabyte of a 48Bit aware OS.

And I wish you every luck in the Universe finding a SATA hard drive with 2K sectors. If you find such which doesn't use 512 Byte emulation and is smaller then 8TB, you can probably use that in your G5. If not, use an external enclosure.
 
I am not talking anymore about larger than 512 byte sectors.

I am saying that it should be possible to boot 8TB drives with APM if the Macs truly use 48-bit LBA (Macs are not crappy PCs) and because pdisk supports 2K blocks.

The partition block size does not need to be the same as the sector size.
 
FAT32 uses a block size of 32K. NTFS uses a block size of 4K. Doesn't work anyways. In order to get one NTFS block, the driver performs 8 reads on the hard drive on the 512 Byte sectors and sums them up to a 4K block.

APM describes a partition starts at LBA 63 and ends at LBA x. The highest x APM can tell is 4294967295. If every sector is 512 Bytes, that adds up to 2.1TB.
Now the ATA driver only knows one function for "WRITE x TO LBA 6348" and one for "READ FROM LBA 321234".

If you call ANY function which reads one 4K block, this function calls the function of the driver 8 times on 8 continuous sectors, append them to a 512Byte block and returns the result.

And 48Bit LBA with 512 Byte sectors result in a maximum disk size of 127 Petabyte.

And about the crappy PCs, the first drive which needs a sector size other then 512 Byte is yet to be announced and there is no trace of it at all, and Linux supports that since last year. I don't even know whether Snow Leopard can handle that, Tiger however definitively can't, I showed you the source code of Mac OS X's XNU kernel.

If the hard drive is a street, LBA is the house numbering. A human brain can only can remember seven numbers in a row (=~20Bit), try to invite a friend to your house at Seagate Street 84769482374958, while he doesn't have no paper to write that down. He won't find it without calling you again. Yes, there is a house at that address. He could go in, take a poop, sleep, eat - but he has to find it in order to do that. If even if he writes it down and has to look it up on a Map (the APM) which stops at number 65536 (=16Bit), he won't find it on that Map and thus won't arrive at your house.

And you want to get your food somewhere else now, like the block level driver for the SATA chipset which provides /dev/rdiskX. Rewrite it to ask the drive for it's sector size (ATA specification provides you with further informations on that) and provide the above 2 functions for variable sector sizes. Do the same for the SATA chipset driver inside the New World ROM. Now your 16TB hard drive with 4K blocks work. Then you want to extent the APM record to 64Bit definitions for your partitions, now every hard drive works. Don't forget to release it. How long do you think would that take? Right, might take some time and there was no need before someone released a hard drive >2TB, that's why all OSs left that specific case unimplemented. Would Apple do that as an update to Tiger and spend time the developers could work on 10.7? I don't think so. Could someone with a little C and Obj-C experience who unlike you get's the core of the problem can do it by himself? Probably. Will it be easier to sell their G5 or put it into the garage and get a Intel Mac? Sure. Is most of the problem solved by an external enclosure on a G3, G4 or G5 and thus not even worth to spend time on the coding? Definitively. Has Apple already fixed it by using EFI and GPT on their Intel Macs? Yes. Does any major or minor hard drive producing company has plans to release any ATA drive that doesn't use 512Byte emulation? I haven't heard about it. Blah blah? Blah. The wheels on the bus go round and round, round and round, round and round.
 
I prefer mirrored drives for storage. It's pretty annoying to have several TBs of data go up in smoke.

I can get two 2 TB drives for roughly the price of one 3 TB disk so it seems rather pointless at the moment. Right now I have two 1TB in RAID1 which quite a lot of space, actually.
 
You have shown code that calculates the disk size based on the number of 512-byte sectors and then goes setting the block size to 4K.

You haven't shown that the Mac can only do 1 sector access per logical block.

And you haven't shown that old Macs trim the 48-bit LBA to 32 bits.

I don't care about PCs.
 
cube said:
You have shown code that calculates the disk size based on the number of 512-byte sectors and then goes setting the block size to 4K.

You haven't shown that the Mac can only do 1 sector access per logical block.

And you haven't shown that old Macs trim the 48-bit LBA to 32 bits.

I don't care about PCs.
Click to expand...

1) Have a look at the code for the SATA controller then.
2) You don't get the whole concept of what a sector and LBA is. If all you do is send "GET Sector/LBA #1234" to the disk and then read 512 Bytes from it, YOU have to explain ME first, on which technical base you want to achieve reading multiple sectors at one address. As to the above example, you can't send a letter to one house if there is a second one that has the same house numbering. Your imagination is limited by the ATA specification.
3) I don't have to, because with APM you can't create partitions that occupate more than a total of 2.1TB on the disk. GPT however can, but the New World ROM can't boot such disks. All I said is that old Macs expand 28Bit LBA to 32Bit integers, then ATA-6 specification expanded LBA for the disks to 48Bit, OSs were converted to used 64Bit integers then and called it "48Bit aware".
If the post says "We can only deliver letters to Houses up to number 100 in Foo Street", try sending a letter to number 105. Yes, there is a house, but the postman won't find it.

4) Macs, PCs, the iPhone, electrical cars, always the same principles if it comes to ATA hard drives, bits and bytes. Oh, and Hugh Jackman. And if you haven't received the memo, Intel Macs are PCs. And I'm rather talking UNIX-compatible than PC, which even you can't doubt, both GNU/Linux and Mac OS X are. If you don't care about PCs, insert "Linux-Based TiVo with ARM-SoC and SATA hard drive" everywhere you mean to see "PC".

You might think Linux=PC, I think of it as a development community in which you can be 100% sure that anyone would have implemented the stuff before 2009 if it was needed, because there would have been anyone who would own such a disk and needed to access it. Same goes for kexts for Tiger, as you can easily develop that yourself by modifying the source code that Apple releases. If you're not that good with the hardware stuff, you may be better off with Photoshoping. Maybe you're more creative then logical.
 
Well, pdisk assigns map->physical_block to the value of map->logical_block if the latter is larger, but then there is a comment that physical_block must be equal to sbBlockSize.
 
Well again, I don't know where the context block size comes from in the 10.5 driver, but everything uses 64-bit offsets, and pdisk doesn't seem to get confused between having a 2K physical block size, and a 512-byte sector size.

Some older ATA drivers used UInt32 block addresses and filled the high part of the LBA with 0.
 
cube said:
Well again, I don't know where the context block size comes from in the 10.5 driver, but everything uses 64-bit offsets, and pdisk doesn't seem to get confused between having a 2K physical block size, and a 512-byte sector size.
Click to expand...
A 2K block is just 4 consecutive 512Byte sectors. They do that kind of stuff so that the heads of the hard drive move less, instead of running wild to find fragmented 512Byte sectors, you group them into 2K blocks so you can read them from one track to increased the throughput of the drive.

cube said:
Some older ATA drivers used UInt32 block addresses and filled the high part of the LBA with 0.
Click to expand...
That's what I called "Expand 28Bit LBA to 32Bit Integers" and "Not aware of 48Bit LBA". Some drivers for early G4 Macs should still do this in Leopard.
 
Many machines prior to June 2002 don't support 48-bit LBA in the firmware, and they can boot from a disk greater than 128 GiB, just don't straddle this border with a partition. When the OS loads, you can access the partitions beyond this limit with the Intech driver.

This machines and newer machines where the fimware might be limited to 32-bit, only need to be able to properly use the 2K-formatted disks upto their own limit, not access the whole disk, for the boot partition.
 
Anybody tried the drive?

Hello. Has anybody tried it with the MBP? Is it working fine under Mac OS, Bootcamp and Fusion?
 
It doesn't fit in there, because it's 3.5". But if you want to use it as an external hard drive or even boot via FireWire, it works fine on your MBP. For Bootcamp with Windows however they work only on Windows7/Vista 64Bit if you want to install it on this drive (On Windows XP x64 it's data disk only, so you'd need to install that on the internal disk anyways).
The whole blathering we did here is only applying to G3,G4,G5 Macs, Intel Macs are fine.

Compiz Fusion or VMWare Fusion work too, however for IBRIX Fusion, a massively parallel file system from HP for computer clusters, there is no informations available.
 
Availability

Is the drive available for sale now? I asked Seagate and the agent wrote "I guess so."
 
OP. Thank you for this write up. I hope that these drives are cheaper then what you say! I might refrain from purchasing some more drives until these come out to drive prices down even more (mwahah).

Also, currently do you know the maximum size the technology will allow the hdds to be? Like CPU transistors, we can't just keep making everything smaller and smaller, so what limitations are we looking at?

hajime said:
Is the drive available for sale now? I asked Seagate and the agent wrote "I guess so."
Click to expand...

If you read the first few posts you would see it would be available later this year.
 
DoFoT9 said:
If you read the first few posts you would see it would be available later this year.
Click to expand...

I keep getting inconsistent info. From newegg, the ETA is 08/10/2010. Does that mean I can get it on August 10 or October 8?
 
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