[TRZ06]

Originally Posted by Hawkeye

All macbooks have that as an option AFAIK. At least the Pro versions do!

I have a Macbook Pro w/ a SSD. I love it!!!

It runs silent (unless the cooling fan kicks on), is more immune to abuse (as most laptops are subjected to, compared to a desktop), it's snappy on start-up and application launch.

Yes, a draw back is over a time frame it will loss cells, but it will still last long enough over what the average life span of a laptop is. As long as you backup (which I do via time capsule daily), if it does die before replacement time, just get a new SSD and do a restore from back-up overnight and it's like nothing happened since time capsule takes a complete image (including settings)

For me (for a laptop) the pros out weigh the cons.

[radix]

Originally Posted by Maestro

SSD are still expense, and the only way to make the cheap is to use MLC flash technology, but as this gets cheaper they become less reliable. As an example the best flash which is SLC you can write and erase data to each cell 100K times before the cell wears out, on the current MLC it is 3K going to 1.5K in the next generation. This works well in an MP3 player since you usually write once and read many times.

3k going to 1.5k? Where did you get those numbers? MLC is specified at 10k writes. Realistically that ranges from 5k to 10k real world for most drives. 30k for eMLC.

http://www.xbitlabs.com/news/storage...te_Drives.html


Honestly though, this does not speak to how long the drive will last as that will depend largely on utilization.

Originally Posted by Maestro

Well in modern PC which are always writing and erasing data you could find that your data is getting corrupted as the device wears out and you get no warning about this either it just happen. Hell some SSD manufacturers turn the SSD in to ROM when it hits a certain wear-out point, which is okay since you did not loose anything but your PC will fail to run since the when booting does try to write to the drive and if can not it fails.

Erasing data? I'm not sure what you mean. If you mean deleting files, that doesn't require much I/O. Simply remove the directory entry for the file and if the inode link count for the file becomes zero, deallocate it. I'd imagine it works similarly with NTFS.

Originally Posted by Maestro

So HDD do fail but their cost per GB is about $0.07 verses SSD at $2.50 and you can write and erase and HDD as many times as you like and never worry if the data is there.

That's just not true. Blocks fail on HDD and they are added to the G-LIST. If the data on the bad block can be recovered the a new block from the spare list is remapped in place of the failed one. Sometimes the data can't be recovered, sometimes it can't. In other words, silent data corruption is not a problem exclusive to SSD.

Originally Posted by Maestro

Yeah as someone pointed out the boot time is fast, but that only true at first over time SSD slow down due to what is know as wear leveling to help reduce one or a group of cells being written all the time, The SSD will start spending lots of time moving data around and this impacts the performance.

It is true that SSD performance will degrade over time depending on usage level. Even still, a worn down SSD will still outperform even 15k RPM drives. Additionally, many manufacturers include a spare (over-provisioned) area with their drives, that can be used for wear leveling.

Originally Posted by Maestro

Basically, it was the Flash memory markets attempt to sell you all more flash and put all your data at risk, It was poor fit and PC industry finally figure it out.

The PC industry is still moving forward with NAND, it's just that the price point still isn't good enough yet. The technology is good enough now, and is still getting better.

Originally Posted by Maestro

You would be better off buying a 7200 RPM drive, it will not be faster on boot up than an SSD but your overall performance will be better and you can get 2 of those drive for the price of a low cost MLC SSD.

Your overall performance will probably not be better with 2 15k RPM HDD that it will with one SDD. I'm not sure what would make you say that. Even the slowest flash is almost an order of magnitude faster than 15k RPM HDD for random access, and still 1.5 to 2.5 times faster for large sequential access. Any NAND drive will outperform a 7.2k RPM drive, easily. It wouldn't even be a competition.

[radix]

http://www.thebuzzmedia.com/intel-x2...nchmarks/#iops


Price: $404:

http://www.newegg.com/Product/Produc...82E16820167017

Price: $190 x 2 = $380:

http://www.newegg.com/Product/Produc...heetah%2015k.6


So for $404 dollar you could get one SSD drive that would probably out perform two HDDs in a RAID-0 configuration. On the other hand, you'd get less about half the usable storage space. Keep in mind that if you're running two drives in a RAID-0 configuration, you have to divide the MTBF for one drive by two.

x = number of drives
y = mtbf for drive
n = mtbf for array

n = y / x


In this case x would be 2, so n = y / 2. Since you're in an unprotected configuration, loss of either drive will result in the loss of data.

[radix]

Originally Posted by kaykay

Just bought a Western Digital 64GB SSD from Newegg.com for about $120-130 or something like that.

Made it a portable HDD via USB (yes, USB 2.0 does slow down the IO performance). Waiting for some USB 3.0 enclosures soon.

SSD's are great, very fast read/write times (although PC Pers did a review vs. a WD Caviar Black and the results were very close). They have MTBF higher than conventional HDDs, data integrity is better, they're a tad bit faster than most drives, great for OS installs on the primary disk.

Something must have been skewed in their test. There is no way a 7200 RPM SATA drive even comes close to the slowest consumer SSD drive performance wise. A 7200 RPM drive should do no more than about 100 IOPs, for SSD drives IOPs measure in the thousands.

[Maestro]

radix,

Did not want to try and respond to each of your points in quotes, however it is obvious you are familiar with the technology, I am too. I Manage mass storage technology for a large company and I use to working as an engineer in a very well known computer company doing drive qualifications as one of my jobs.

No SSD today is using NAND flash with 10K write and erase cycles those were based on 56nm technology which were taken off line last years by all the manufactures Toshiba being the last. Today they are all shipping 34nm technology and it has 3K cycles, and they are moving to 2Xnm technology next year it will have 1.5K.

You mention the eMLC as having 30K, which it true but the way they are achieving this is by slowing the device down, there is more to it than that but that is the basic approach which mean the it will not preform as well.

Another important point with SSD, they should not be spec on write and erase cycles which they had avoided talking about but will share if asked, they should be spec on total GB transfer and still maintain specifications. I been asking for this for years and they are now specing the SSD this way and you would be surprised. Basically, you can transfer so much data and then the device starts to drop in performance or it is wore out can not be use, not the case with HDDs time and POH is the limiting factor on HDD but not how many bits you can write.

Imagine if every car on the road stopped working at 100K miles not to be fix or usable, that is what you get with SSD.

Also the links you list are Intel propaganda and I will it at that.

Your correct HDD have blocks that fail, and the HDD moves data around and spare the blocks out and some times you get an unrecoverable error, just the fact of life with HDDs, but HDD do not wear out like SSD do. You can write a block on an HDD millions of times and it will not degrade just because of the bits being flipped.

What I mean by erasing data is the SSD as part of their wear leveling algorithms move data around to all the cells and every time it changes the data or flips the bit in a cell it is a write and erase cycle. Also as the OS creates and deletes scratch and temporary file this adds to this problem.

Now on performance, I personally have not see any data from any manufacture demonstrating the performance of their SDD over time, as it is worn, as it is filled to capacity. I have asked for it from Intel, Toshiba, SanDisk, Samsung, and Micron, oh by the way Intel uses Micron Flash and none of them can backup their claims other than how it performs new out of the box.

NAND Flash is dying as an industry, unless they can solve the data reliability problem, it will continue to useful in products like MP3s but any device that has what is called data turnover can not use it beyond the current technologies.

nTo all SSD are the same, there are only 4 companies who make Flash and 50 companies making SSD, some have a clue and most have no idea what they are doing. Personally, buying SSD from companies like WD, Seagate or Toshiba is good since they understand the entire storage industry and understand data integrity issue due to their 30 years of HDD experience. Everyone else is just trying to sell you a product.

I am not saying SSD are bad, I am saying it depends on the application and that most consumers have no clue about it. They see and hear all the great things about SSDs, but much of it is based on SLC technologies, drives that use a combination of SLC and MLC technologies or also incorporate SDRAM. Yes you can get 64GB SDD in the $150 price range but it does not have the performance you think, you are going to be spending more like $500 to $1000 for high performing SSD that can keep up with a server class drive you showed.

I personally rather use a HDD with a back up than spend 3X on a SSD and then buy a HDD to back up still.

[blue2fire]

I don't want to pay $600 for a 256GB drive, regardless of it's efficiency, NVH or speed. As with everything, wait till it proliferates. Companies are not really thankful to early adopters.

[radix]

Originally Posted by Maestro

radix,

Did not want to try and respond to each of your points in quotes, however it is obvious you are familiar with the technology, I am too. I Manage mass storage technology for a large company and I use to working as an engineer in a very well known computer company doing drive qualifications as one of my jobs.

No SSD today is using NAND flash with 10K write and erase cycles those were based on 56nm technology which were taken off line last years by all the manufactures Toshiba being the last. Today they are all shipping 34nm technology and it has 3K cycles, and they are moving to 2Xnm technology next year it will have 1.5K.

You mention the eMLC as having 30K, which it true but the way they are achieving this is by slowing the device down, there is more to it than that but that is the basic approach which mean the it will not preform as well.

Another important point with SSD, they should not be spec on write and erase cycles which they had avoided talking about but will share if asked, they should be spec on total GB transfer and still maintain specifications. I been asking for this for years and they are now specing the SSD this way and you would be surprised. Basically, you can transfer so much data and then the device starts to drop in performance or it is wore out can not be use, not the case with HDDs time and POH is the limiting factor on HDD but not how many bits you can write.

Imagine if every car on the road stopped working at 100K miles not to be fix or usable, that is what you get with SSD.

Also the links you list are Intel propaganda and I will it at that.

Your correct HDD have blocks that fail, and the HDD moves data around and spare the blocks out and some times you get an unrecoverable error, just the fact of life with HDDs, but HDD do not wear out like SSD do. You can write a block on an HDD millions of times and it will not degrade just because of the bits being flipped.

What I mean by erasing data is the SSD as part of their wear leveling algorithms move data around to all the cells and every time it changes the data or flips the bit in a cell it is a write and erase cycle. Also as the OS creates and deletes scratch and temporary file this adds to this problem.

Now on performance, I personally have not see any data from any manufacture demonstrating the performance of their SDD over time, as it is worn, as it is filled to capacity. I have asked for it from Intel, Toshiba, SanDisk, Samsung, and Micron, oh by the way Intel uses Micron Flash and none of them can backup their claims other than how it performs new out of the box.

NAND Flash is dying as an industry, unless they can solve the data reliability problem, it will continue to useful in products like MP3s but any device that has what is called data turnover can not use it beyond the current technologies.

nTo all SSD are the same, there are only 4 companies who make Flash and 50 companies making SSD, some have a clue and most have no idea what they are doing. Personally, buying SSD from companies like WD, Seagate or Toshiba is good since they understand the entire storage industry and understand data integrity issue due to their 30 years of HDD experience. Everyone else is just trying to sell you a product.

I am not saying SSD are bad, I am saying it depends on the application and that most consumers have no clue about it. They see and hear all the great things about SSDs, but much of it is based on SLC technologies, drives that use a combination of SLC and MLC technologies or also incorporate SDRAM. Yes you can get 64GB SDD in the $150 price range but it does not have the performance you think, you are going to be spending more like $500 to $1000 for high performing SSD that can keep up with a server class drive you showed.

I personally rather use a HDD with a back up than spend 3X on a SSD and then buy a HDD to back up still.

Even at 3000 write cycles, it's still not that big an issue, here's how the math works for a 160GB drive:

lark ~ % bc -l
bc 1.06
Copyright 1991-1994, 1997, 1998, 2000 Free Software Foundation, Inc.
This is free software with ABSOLUTELY NO WARRANTY.
For details type `warranty'.
160 * 3000 / 1.5
320000.00000000000000000000
320000 / 40
8000.00000000000000000000
8000.00000000000000000000 / 365
21.91780821917808219178

The forumla was gleaned from this article:

http://techon.nikkeibp.co.jp/article...090528/170920/

AFAICT, the 1.5 number is probably the product of coefficients for both wear leveling and write amplification, if I had to guess. Nevertheless, that's 22 years for a drive with a write endurance of 3k per cell for a user that writes 40GBs of data per day.

http://techreport.com/articles.x/15433

If you don't want to crunch through the math, Intel estimates that the 80GB X25-M will last for five years with "much greater than" 100GB of write-erase per day. That's a relatively long time for much more data than most folks are likely to write or erase on a daily basis.

The drive in question has a 55nm process size however. Still, most users don't write half that much, and this still doesn't even account for over provisioning. Most companies that use flash use SLC drives, because they can afford to. MLC, even at 25nm is probably fine for consumers.