Two questions for SSD experts

So I upgraded my Precision M4500 to a C300 SSD. I really couldn't be bothered to do a fresh install on the SSD, so I made a disk image of the hard drive (which is based on Dell's original image on the machine). The SSD seems to be performing nicely, with a 15-second boot to the welcome screen (quite a bit of software installed, about 90 processes running right after startup, and counting from the end of POST; POST time itself seems to have increased by a couple of seconds), and a WEI disk score of 7.8. So I think I don't have anything to complain about performance-wise.

Now here are my two questions:

- I have seen people mentioning the importance of a 1024kB partition offset. I checked, and my disk starts with the Dell Diagnostics partition at a 31kB offset, and the actual system partition is some 30MB down. Will this situation impact performance? I know how to use partition managers, so I guess I could move stuff to obtain a 1024kB offset, but I'm not sure anything could be gained from that. Like I said, the disk seems to be doing just fine right now. While we are at it, can anybody explain why that 1024kB offset might be beneficial?

- I usually do backups via Acronis disk images. When I run into a serious problem, I simply restore the disk image, overwriting the whole disk with a known good configuration. I wonder how this procedure might affect the performance, or even the life of an SSD. For the sake of argument, let's say I currently use 100GB of the 256GB on that C300. I decide that I need to restore a disk image, so I boot from the Acronis image, which loads a version of Linux that probably knows nothing about TRIM, SSDs, or anything of that sort. During restore, all Acronis does is simply write the sector addresses stored in the disk image to the SSD. That means, I think, as far as the SSD is concerned nothing is deleted, no TRIM commands issued, ever, just new data written to the drive. With the SSD using wear-leveling, my guess is that after that restore almost all of the disk has some non-zero data in it, with half of the data just old junk. Can anybody comment on the potential performance impact of this procedure? What if I had to do this often?

As an aside, I strongly feel issues like the above really demonstrate that SSDs are not quite ready for prime time yet, and are clearly at the bleeding edge right now. People shouldn't have to baby a low-level piece of hardware like this; most certainly, nobody should have to waste a thought on details like partition alignment, or whether or not zeroes are written to whatever memory cells on an SSD...

 

http://forum.notebookreview.com/alienware-m11x/516919-question-about-upgrading-hdd.html#post6688754

Before I fired up my AW M11x R2 for the first time I imaged the hard drive with Acronis. I also checked the partition alignment of the standard Dell layout using Paragon and found something interesting:

The first partition that Dell creates isn't partition-aligned, but the other two are, which is weird because typically, if your first partition isn't partition-aligned, then each additional partition you create after the first one will be misaligned as well. Dell went through the trouble of calculating the offsets of the 2nd and 3rd parititions so that they would be properly aligned. I don't know why they just didn't align the first partition so the others would fall into alignment automagically.

The partition-alignment problem was bad with the first and second generation SSD controllers. I personally partition-align every drive I touch unless there is some PITA reason why I can't. Due to the more advanced controllers in the latest generation SSD's, the problem is mitigated.

Your alignment doesn't have to be 1024, It can be 64, 128 or any multiple of 128, but 1024 provides the best compatibility if you mess with different Stripe sizes when doing RAID as well as different File Allocation Unit sizes according to MS.

This isn't just an SSD problem btw, it affects all disks. It's not a problem if you're using Vista, Win7, or Server 2008 to create partitions. It's an Acronis problem because it doesn't honor partition offsets of the host disk when you create an image. File-based disk imaging products are a better solution to the problem.

As I stated in the thread I linked, Acronis is foaming at the mouth to get my company's business (we are rather large), and they've yet to get it because they STILL can't implement proper partition-alignment into their products.

EDIT: Found the picture I took using Paragon alignment-checking tool on Dell's default partition alignment.

 

To check the alignment you can also use this calculator:
SSD Alignment Calculator | techPowerUp

Another free solution for disk cloning is the dd program (unix), check a couple of examples here:
dd (Unix) - Wikipedia, the free encyclopedia

 

Pirx,

I would recommend aligning the partitions for your SSD - if you think it is fast now, this will make a huge difference (to keep it fast as your drive fills up).

Also, as noted, Acronis does not honour proper (aligned) offsets.

I would secure erase the SSD and do a clean install of Win 7 which will properly partition the SSD to ensure that it is aligned from the start.

Have to agree with you about SSD's not being prime time yet - they still have a long way to go - hopefully, they will cover that long road in a short period of time - (when they're fast - they're very fast!).

Quote:
"With 4K-alignment the 3.0Gbps speeds changed to 256MB/s read and 194MB/s write."

Source:
Crucial RealSSD C300 Review (256GB) | StorageReview.com

Good luck.

 

Very interesting information, thanks!

Well, it seems it does if you restore entire disks, and probably also 1:1 partition restores onto the same disk.

That is out of the question. A clean install plus install and configuration of all the software on this box takes several days of work, full time. Not something I am going to do to gain a couple of fractions of a second here or there. I might try to use Paragon's partitioning tool, however, if I am convinced there is a tangible benefit in the real world. I have my doubts, however.

Yes, but at a price, which is not only monetary, but additional time that the end user needs to spend to take full advantage of them. That time is a lot more valuable than the monetary cost of the drive...

Thanks! Do you happen to know the parameters (NAND Erase Block Size, NAND Page Size) for the C300?

 

P.S.: You were right, I just checked, and my system partition is properly aligned, so I'm good on that front.

 

Use the default ones Pirx