Backup cloning from 512 byte/sector HDD to 4KB/sector HDD

[New7user7]

I'm trying to educate myself on cloning i.e. bootable sector-by-sector replication, not just creating an image file of the used disk space. So far, I've bought a high performance HDD of the wrong size, trying to make sure that I replace it with an HDD with which my first cloning attempt will go without a hitch.

My laptop contains a 640GB Toshiba MK6465GSX HDD (Toshiba SDD - Product Detail). I am considering getting 640GB WD Scorpio Blue HDD for the cloning.

One of the constraints I want to observe is that I should be able to pick it up in person from one of the retailers in my city. However, they invariably carry the WD6400BPVT variant, which uses 4KB sectors ("Advance Format"). Nothing comes up in a search for "MKxx65GSX MKxx76GSX advanced-format" (without quotes), so I assume it has 512 byte sectors.

Is there a problem with cloning from a 512 bytes/sector HDD to an 4KB/sector HDD?

 

[JimLewandowski]

Since the currently available advanced format drives use emulation as if they are 512-byte sector drives, I would think that would make you immune from any issues here. IOW, I assume the AF controller would see (likely) contiguous 512-byte sectors of information to read/write and knows to group those to equate to a 4096-byte physical sector. Or, read of a single 512-byte block requested by Windows would have the controller read a whole 4096-byte sector, and return only the appropriate 512 bytes of it (1 of 4 chunks depending on sector/LBA).

http://forum.storagecraft.com/Community/forums/p/3864/18135.aspx

Interestingly, the advanced format drives now have the same potential issues as SSDs re: alignment of partitions.

 

[New7user7]

Is there typically a bandwidth penalty in the translation? I got that warning in another forum.

I read your link, and not having done partitioning, imaging, cloning, or formatting (aside from blindly following tech support instructions), it's a big foggy. I'm sure it will make more sense after my first cloning, which I'm trying to ensure is done right.

 

[JimLewandowski]

Is there typically a bandwidth penalty in the translation? I got that warning in another forum.

I read your link, and not having done partitioning, imaging, cloning, or formatting (aside from blindly following tech support instructions), it's a big foggy. I'm sure it will make more sense after my first cloning, which I'm trying to ensure is done right.

By bandwidth do you mean performance penalty for accessing a 4096-byte sector drive? Well, technically, yes IF there are some READ requests that are less than 4096 bytes as a whole 4096-bytes would have to be read vs. just <4096 bytes. This normally wouldn't apply to writes as they are asychronous events UNTIL cache is full.

.

 

[New7user7]

OK, this will sound dumb, but I don't know what I meant by penalty. I was told that there was a potential for performance degradation in reading and writing, but I wasn't sure whether that meant in making the clone or booting up and using the clone. From what I've surfed so far, there seems to be alignment issues that one has to tend to in cloning to Advanced Format drives, so I just assumed it had to do with that. I actually plough through the tech talk, but it doesn't make a whole lot of sense to me right now.

Regarding what you said about reading 4KByte to access a smaller chunk of data -- I'm not sure how that becomes a penalty, since you would have to read a sector regardless of its size. Unless it takes longer to read 4KByte (though I'm guessing that the read time wouldn't differe since it's the same number of revolutions of the platter -- I might be totally of the mark about how HDDs physically work).

 

[JimLewandowski]

It takes 8x longer to read a 4096-byte block vs. a 512-byte one (disk has to spin 4K past the read/write head vs. only .5K). However. most Windows I/Os are 4K or greater so it's not really a discernible, measureable issue.

Yes, you need to align an Advance Format drive on a boundary like you do an SSD drive.

If you are cloning a drive, the vast majority of I/Os will be sequential (outright or pseudo-sequential). No worry other then the alignment issue.

To summarize: for the rare < 4K-byte reads, you will be paying a miniscule penalty (< 1 millisecond or about one HALF of 1 millisecond = .0005 seconds). For 98% of your Windows-based I/Os, you won't pay any penalty at all.

 

[New7user7]

Darn, looks like there's no way to magically avoid alignment issue. Not that it's necessarily complicated (I'm not sure how complicated it is), it's just that it involves an extra step which (from my surfing) usually means getting to know a tool from the HDD manufacturer. And it means that many more things can go wrong e.g. parameters & switches for the tool. Also, I'll be using the Advanced Format HDD as my main drive, and using the current 512 byte/sector drive as the externally housed bootable cloning target. So I'll be exploring whether there are issues related to sector size in going from Advanced Format to 512 bytes/sector as well (if you have any comments, I'd appreciate them).

Thanks for the heads up. I will search for a tool from the manufacturer of the wrong-sized HDD that I bought (500GB Seagate Momentus XT). As it turns out, it might not be the wrong size, even though it is smaller. A friend said that he has cloned to smaller drives before, and all went well (even with nonmatching sector sizes). I suspect that the app he used took care of many of these details such as sizing and sector alignment. If I can't get a warm fuzzy feeling about how to deal with such things in a simple way using freeware, I'll spring for Ghost as well.

 

[New7user7]

Looks like Seagate has a new SmartAlign algorithm in their firmware to make their Advanced format HDD look like 512 bytes/sector. However, it's not clear what drives contain this algorithm. It relieves alignment problems between the OS & the HDD, but it isn't clear that it does so for cloning (either from the Momentus XL to a 512 bytes/sector HDD or vice-versa -- I'll be doing both).

 

[FranklinBoyce]

I want to clone from a 250GB Hitachi to a 1TB Samsung/Seagate.

What do I need to do to get the alignment right?

A first attempted failed.

See: http://www.sevenforums.com/backup-r...boot-after-disk-cloning-error-0xc000000e.html