Advanced Format not working with Win 7 dynamic disk RAID1?

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spotpuff

Gawd
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I created a software based RAID 1 in Windows 7 on my Gigabyte P55A-UD4P. The drives are connected to the board's Marvell 9210 controller, but are set up as individual drives in the BIOS, not as a RAID array.

On my old motherboard, a gigabyte 965p-ds3, the drives were on that motherboard's RAID ports (I believe they were JMicron), and while the disk size was the same, data on the drives used less space.

For example when checking file properties, a 500MB file on the old drive might take up 500MB but on the new drive would take up 455MB (this is consistent with what I thought advanced format would do).

However, on the new motherboard, the drives connected to the Marvell controller and then set up as RAID 1 are showing the same size on disk as drives without advanced format.

Does anyone know any reason why this is happening? I thought Windows 7 was supposed to handle Advanced Format without the need for additional software, and it did work on the older motherboard.
 
Can you explain to me what you think Advanced Format really is? I'm particularly confused by this statement:

For example when checking file properties, a 500MB file on the old drive might take up 500MB but on the new drive would take up 455MB (this is consistent with what I thought advanced format would do).
Click to expand...

A 500MB file will take 500MB on disk; there is no other way. If you enable filesystem compression, you change the size of the file; but that probably was not what you meant.

Advanced Format uses 4KiB sectors instead of 512 bytes. So it is important you created the partition using WINDOWS 7 instead. So the question is, how did you create the partition on this drive, and can you check alignment with AS SSD benchmark on your EARS drive.

You seem to be confused about what Advanced Format is and how it works. However, it shouldn't change the free space available on your drive.
 
Advanced format as I understand it is a way to use 4KB sectors on hard disks instead of 512B sectors to store data.

On my old motherboard, I attached 2 2TB WD EARS drives to the motherboard RAID ports, created a RAID 1 array, and then created a 2TB partition in Windows. The partition showed up as 1.86TB due to Windows formatting.

This confused me at first as I thought advanced format was supposed to make drives have more usable space, so I thought the figure should be 9% (or 11%?) higher, but it was exactly double the old 1TB non-advanced format drive I had.

However, what I noticed is when I copied files from the older 1TB drive to the new 2TB RAID1 array, the "size on disk" was different. As in the example I gave, a 100MB file on the non advanced format drive would only take up 91MB on the new drive.

If this is not how advanced format is supposed to work, then I'm wrong, but that's what I was seeing.

On the new motherboard however, I tried two approaches:

1. re-create the RAID array (after numerous headaches with the on-board raid controller). Initially I tried creating a RAID1 virtual disk in the BIOS, then intialized the disks as GPT in disk management and created a 2TB partition on the drives (or slightly smaller due to overhead). Again, the drive shows as 1.86TB.

2. used both drives attached to the RAID controller as single disks and created a RAID 1 in Windows using disk management, again 1.86TB.

However, under both of the above approaches, copying a 100MB file from the non-advanced format drive still resulted in a 100MB file on the advanced format RAID 1 array.

Maybe it's because I didn't use 4kb sector when formatting? (allocation size?) I forget, but I will try again tonight I guess.

I am unfamiliar with the AS SSD tool, so if you can tell me what I should check or how to check alignment in it I will do so later.

http://www.alex-is.de/PHP/fusion/downloads.php?cat_id=4 that's the link right?

A 500MB file will take 500MB on disk; there is no other way. If you enable filesystem compression, you change the size of the file; but that probably was not what you meant.
Click to expand...

When I say 500MB file, I mean on a non-advanced format drive it was taking up 500MB. As I understand it there is overhead involved in that 500MB. So if moved to an advanced format drive (ugh, I'm just going to abbreviate this AFD from now on) the overhead is reduced, and what WD claimed was a 7-11% reduction and what I saw was an approximately 9% reduction in "size on disk", as in the 500MB file would only take up 455MB on the AFD. You are correct; I did not enable disk compression.

Again, I could be incorrect, but based on the fact that the 2TB drive was showing up as 1.86TB in both cases, if files don't take up less space on disk on AFD then how are you going to get any "usable space" improvements?
 
On my old motherboard, I attached 2 2TB WD EARS drives to the motherboard RAID ports, created a RAID 1 array, and then created a 2TB partition in Windows. The partition showed up as 1.86TB due to Windows formatting.
Click to expand...

This is the expected result. 2TB hard drives are really 1.86GB because the of the way HD sizes are stated not because of formatting.
Read this thread about capacities:
http://hardforum.com/showthread.php?t=1347640
 
Last edited:
drescherjm said:
This is the expected result. 2TB hard drives are really 1.86GB because the of the way HD sizes are stated not because of formatting.
Read this thread about capacities:
http://hardforum.com/showthread.php?t=1347640
Click to expand...

I know that, the part I'm wondering about is advanced format and why it was reducing "size on disk" previously but does not appear to be doing so now.

I did not expect a 2TB disk's capacity to increase because it was an AFD, just "usable" capacity.
 
You probably read that Advanced Format makes more efficient use of the platter capacity and achieve higher data densities. Another way of saying this, is to say that it is easiest to make a 500GB-platter disk with Advanced Format than without Advanced Format. Without Advanced Format the data density has to be higher to achieve the same 500GB-per-platter.

This has to do with unused space on the platter between each sector. So if sectors are 512 bytes but you have ~100 bytes between sectors essentially wasted/unusable, then you have about 20% lost space due to inefficient use of the platter real-estate. Advanced Format will make sectors bigger, meaning less sectors, also meaning less unused space between the sectors.

So to make things simple; advanced format doesn't change anything for the user; it is easier for WD to create 500GB disks with Advanced Format.

The only thing you need to do as user, is make sure the drive is aligned. You should create a partition on the drive using Windows 7 or Vista. You did not specify your OS as of yet. If this is XP, then you're out of luck. XP does not work well with 4KiB-sectors in fact its the sole reason the EARS is not a REAL 4K sector drive; it advertises itself as 512 byte sector drive in order to not confuse XP which does not support any HDD other than having 512 byte sectors.
 
sub.mesa said:
You probably read that Advanced Format makes more efficient use of the platter capacity and achieve higher data densities. Another way of saying this, is to say that it is easiest to make a 500GB-platter disk with Advanced Format than without Advanced Format. Without Advanced Format the data density has to be higher to achieve the same 500GB-per-platter.

This has to do with unused space on the platter between each sector. So if sectors are 512 bytes but you have ~100 bytes between sectors essentially wasted/unusable, then you have about 20% lost space due to inefficient use of the platter real-estate. Advanced Format will make sectors bigger, meaning less sectors, also meaning less unused space between the sectors.

So to make things simple; advanced format doesn't change anything for the user; it is easier for WD to create 500GB disks with Advanced Format.

The only thing you need to do as user, is make sure the drive is aligned. You should create a partition on the drive using Windows 7 or Vista. You did not specify your OS as of yet. If this is XP, then you're out of luck. XP does not work well with 4KiB-sectors in fact its the sole reason the EARS is not a REAL 4K sector drive; it advertises itself as 512 byte sector drive in order to not confuse XP which does not support any HDD other than having 512 byte sectors.
Click to expand...

Using Windows 7 so the partition creation shouldn't be an issue.

Regarding AFDs, the only advantage is to the manufacturer then? It makes it "easier" to make larger drives because there's less wasted space on the disk going to overhead? I thought the 11% more "usable" space would be passed on to users, or at least be visible when comparing files stored on AFD vs non-AFD drives. But as I said, I could be wrong, and it looks like I am, so point taken.
 
No a 500GB disk is still a 500GB disk. I think Advanced Format may cause to see 666/750GB-per-platter disks sooner than without Advanced Format.

The advantage to the user is the reliability aspect; with more checksum data available per sector, the reliability of an Advanced Format drive should be higher than one of the same type without Advanced Format. So you might see less bad sectors or I/O timeouts, thanks to the Advanced Format feature.

It may also add performance, though this is limited as the current drives still advertise themselves as being 512-byte sector drives, in order to stay compatible with Windows XP. The jumper on the drive will correct alignment on XP by a dirty hack; do not remove or set the jumper if your drive has data on it; it may be destructive if you boot the system after changing the jumper; as all LBA addresses have changed.

As long as you create the partition with Windows 7 and not some third-party utility like cloning programs, you should be fine as far as alignment goes.
 
From HotHardware:
Debunking the Myth of Additional Drive Space
We want to clear up some confusion regarding the near-term benefits of Advanced Format. In Western Digital's whitepaper on the subject (PDF), the company states that it can "gain approximately 7-11% in disk space" by using Advanced Format. ECC accounts for 5.5 percent of this; the rest is presumably a mix of efficiency gains in other areas. This has been misinterpreted in a number of circles as meaning that an Advanced Format HDD offers more storage capacity than a normal one. It doesn't—or at least, it doesn't yet. A WD10EARS and a WD10EADS have exactly the same unformatted capacity and Windows reports both drives offer 931GB of storage space.

Western Digital isn't lying about the efficiency benefits of a 4K sector drive, but the company can use that space in a number of ways. Smaller platters are one option, larger storage capacity is another, and removing the innermost tracks of the platter is a third. This last contains an extra bonus—because read and write speeds are typically reported as an average, knocking off the slowest tracks would make the hard drive look faster in a benchmark without actually changing performance at all. For now, WD isn't claiming that Advanced Format delivers any particular advantage and AF drives aren't carrying much of a premium, if any.
Click to expand...

Link:
http://hothardware.com/Articles/WDs...vanced-Format-Windows-XP-Users-Pay-Attention/

So, you were right, no idea what I was smoking before, but I guess for now it's pointless to the user other than higher reliability and possibly higher transfer speeds. Would it matter if my NTFS is allocated at 4096 Bytes or whatever for the allocation unit?

Thanks for the help, btw, helped clear a lot of things up for me.
 
The default settings should be fine, as your system disk handles mostly small files. Though i never did such NTFS benchmarks as i'm mainly a Linux/BSD guy.

The only thing really important with the new EARS drives is alignment. When not aligned, the HDD will internally correct this but this will decrease performance significantly.

If you want to check whether alignment is okay you can download the utility AS SSD, a benchmark used for SSDs. This also checks for alignment, and should say something like 1024K - OK and not 31.5K - BAD.
 
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