Flash-Based Hard Drives Cometh

[gwolfman]

Of course, the hybrid devices might never come out, and SSD might just become the HD replacement in a couple of years.

They already are out!

 

[diabloazul126]

Aren't SSD still prone to finite write/rewrite bits? (So after like 100,000 or 1,000,000 write/rewrites the block just dies.) Or have they managed a way around that?

Until they do, I don't think SSDs will be a viable alternative to standard HDDs. Or at least prolong the lifespan to match disk based drives.

 

[gwolfman]

Aren't SSD still prone to finite write/rewrite bits? (So after like 100,000 or 1,000,000 write/rewrites the block just dies.) Or have they managed a way around that?

Until they do, I don't think SSDs will be a viable alternative to standard HDDs. Or at least prolong the lifespan to match disk based drives.

It's dynamic though. The technology/algorithms exists where they can write to different cells and space out the write operations so it's not on the same one over and over again. Also so devices include extra space so when/if a cell (can't remember the correct term) goes bad it'll automatically move over to a new unused space.

 

[cyberjock]

First, I thought this article was very well written and a GREAT explanation for how useful/worthless this technology is for it's price and your purpose for it. Here's 1 little recommendation...

Quote from the article:

As command queues increase, the single hard drive does not even scale up, as this flash-based HDD does not support command queuing.

When I read the article and saw that, my first response was 'OMG.. the latest and greatest technology with no command queuing?'. Then after thinking about it, command queuing is pointless for flash based technology as you do not have any reason to 'optimize the order of operations' for flash memory. It's basically the same for anything anywhere. It would be nice if you write a comment that although it doesn't support command queuing, if it did the benchmark wouldn't change anything.

Now, on another note, write caching in OSes. If you have data stored in the cache of the hard drive itself to be written and the computer blue screens(reset button hit, whatever) is the data wiped or is the data written? What does the hard drive go through when the machine reboots? Does it execute some kind of 'write cache flush to disk' command? And what does the Flash drive do? I'm just thinking in terms of stability is 1 better or worse for write caching. Obviously write caching random writes on a flash drive will yield the biggest gains.

And heck for that matter, if windows XP(and linux for that matter) has a serious system error, does it flush the write cache before it reboots or is the data lost to the ether forever? I've always wondered these things, and I guess this is a good time to ask.

Thanks

-Cyberjock

 

[Egregious]

Most RAID algorithms are based on identical HW, writing a block to each drive, getting return results, writing another block to each drive, etc. Mismatched HW would move you to 2x the slowest drive at best, since the controller would be waiting on the slow drive all of the time.

Before NCQ was integrated into HDD's RAID controllers used to perform similar functions, and some high end RAID setups used HDD's with synchronized spindles, so that HD1 and HD2 were always reading or writing the same block off of a drive with no seek differential. Software RAID and new low cost RAID controllers ignore all of those mechanical optimizations, and that's part of the reason why a PERC or other high end RAID controller will have greater performance with the same drives.

Different algorithms might be able to take advantage of an HD/SSD combo, like Vista's Speedboost or whatever. Also, the hybrid HD/SSD's that have been predicted in tech news posts could be very high performance with the right algorithm. If you did have a 4GB SSD and a 100GB HD in one device there would be a learning curve on the algorithm as it figured out what sectors were hi read/lo write, so it would be hard to benchmark too..

Of course, the hybrid devices might never come out, and SSD might just become the HD replacement in a couple of years.

Well I could see it being done with a more intelligent raid 1 controller that keeps track of recent data that hasn't been mirrored yet to the second flash drive. It could write to the platter hard drive(best performance) and if there is a request for said data before the mirroring, the fetch would be from the most recent data based on best performance. The mirroring could happen during idle time.
On the other hand the manufactures could just build drives with mega huge caches with non volatile ram.

 

[Sq7]

These flash chips are 2GB apiece. I think that's as state of the art as it gets right now. I don't think it would be cost effective for them to use 256 128MB chips, and the largest capacity chips will be the newest tech with the fastest read and write times, so using more lower capacity chips would not scale the same.

They could scale up to 64, 128, etc GB with more chips, but if people aren't going to buy a $500 HD replacement they probably won't buy a $1-2K HD replacement either.

I'm not so sure. Are the 8GB thumb drives you get everywhere these days based on a different type of flash chip? The 2GB versions are all dirt cheap these days. 1GB even more so. In any case. I was reflecting more on the number of chips per drive. Why not give two options? One with the standard number of chips and one with double the number running in parallel Surely this should be cheaper to make than two separate drives. And therefore cheaper to buy in the end. Are there any technical problems with doing so? I can't imagine there is. All you end up with is exactly what RAID does, except there should be less overhead. Also less travel distance for the data. What is preventing them from going this route.

I think 32x1GB chips should give double the performance that 16x2GB chips can deliver. And 32GB is a sweet spot as far as I am concerned. For the personal computer at least. The main aim in my mind would be to install only the operating system on it and keep the rest of the space reserved for paging. The Documents and settings and program files folders can be mapped to a standard ATA/SATA drive, preferably SATA150. This should speed up boot time, OS HD IO operations and the traditional page file bottleneck. In short. It would speed up everything that matters for a PC user.

 

[Computer_Lots]

I'm confused as to why these things cost so much. I can get a high performance, name brand 16 GB compact flash card for $150. This is for the 133x flaver which I believe is the fastest available. 2 x 150 = 300, not 500. Granted, they have to build in the SATA or PATA interface but surely that doesn't cost $200.

In response to Sq7's comment about 2 drives in RAID vs double the chips on 1 drive. The only advantage I can see to a RAID config is double the interface bandwidth. Of course, if you use SATA 300, then it wouldn't make a difference since these babies only read at 70mbps each. .... "ONLY"

 

[ElKeeed]

I have some experience with running windows off of compact flash and although its very fast there are disadvantages. Unless you do something to minimise writes like install EWF then windows will kill the card in a matter of days.

Have they done something to solve this problem with this device or is it still a huge drawback that has been overlooked?

 

[zenmaster]

What about RAM Drives like the i-RAM.
I'm surprised we are not seeing more devices like this that support 16gb or more RAM as well as faster DDR2 memory.

Sure the price would be crazy, but for real speed freaks could see people going for it. Especially since the performance difference would be crazy. Just imagine running your DB from a drive like that.

Of course you would need serious backup, but it would rock.

 

[gwolfman]

I have some experience with running windows off of compact flash and although its very fast there are disadvantages. Unless you do something to minimise writes like install EWF then windows will kill the card in a matter of days.

Have they done something to solve this problem with this device or is it still a huge drawback that has been overlooked?

What program is EWF?

 

[mgr]

First time on the Forums and not sure how to add a message into the discussion...I seem to find only choices to Reply to specific messages, so apologies if I've got it wrong.

I'm a long time computer and Photoshop user, but not a techie or someone who builds his own machines. I will soon be taking my first steps into HD video editing (serious amateur not pro), and a 2x SanDisk SSD 5000 RAID 0 setup sounds like a great way to go, but I've not been able to find a system maker who includes SSDs in its options list (Dell seems to but only in its laptops). So...I'm looking for advice on makers that are including SSDs as drive choices.

Also, (I know this isn't the place) any system advice on setting up a machine for optimal Photoshop and HD video editing would be great, or pointers to a good user forum where I can learn about it.

Many thanks, _/\/\ichael{R}

 

[flasher702]

However, the relative low power-consumption performance isn't because of the flash technology, but is due to the interface. The new SanDisk drive uses a Serial ATA/150 interface that consumes 0.5 W when idle, which is 10 times higher than the power consumption of the Samsung device, which consumes 0.05 W when idle.

Does the drive not support SATA power saving capabilities? It should be able to power the phy down and save more than a measly .6w between active and idle.

 

[bmichener]

I have a question for those more generally knowledgable about hardware than myself. I recently read an article about stable video editing, which I do quite a bit of. The author recommended keeping a separate hard drive or partition for the OS to keep any junk from building up that could interfere with the video clips.

I have started to look into building a new system and am keeping this advice in mind. Because I am doing storage intensive work it will be a long long time before I will be able to go all flash.

I was thinking about buying a 16bg or 32 gb flash drive for my OS (XP for now) and then using a normal drive for everything else.

The performance drawback to the flash drive seems to be the slow write speeds, and my assumption is that the OS wont do much writing and so should run quite well on a flash drive.

Does this plan makes sense?
Would it make any noticeable difference?

Thanks

 

[gwolfman]

I have a question for those more generally knowledgable about hardware than myself. I recently read an article about stable video editing, which I do quite a bit of. The author recommended keeping a separate hard drive or partition for the OS to keep any junk from building up that could interfere with the video clips.

I have started to look into building a new system and am keeping this advice in mind. Because I am doing storage intensive work it will be a long long time before I will be able to go all flash.

I was thinking about buying a 16bg or 32 gb flash drive for my OS (XP for now) and then using a normal drive for everything else.

The performance drawback to the flash drive seems to be the slow write speeds, and my assumption is that the OS wont do much writing and so should run quite well on a flash drive.

Does this plan makes sense?
Would it make any noticeable difference?

Thanks

Where (on which drive) will you keep your windows swap file?

 

[mgr]

With standard hard disks it makes sense to have separate drives for swap files (with Photoshop I've always had separate drives for both the Win swap file and Photoshop's. But with the near instant speed of an SSD, would I be wrong in thinking that separate drives for swap files are no longer important? Specifically for HD video editing, what drive setup would you recommend without going to overkill?

 

[gwolfman]

With standard hard disks it makes sense to have separate drives for swap files (with Photoshop I've always had separate drives for both the Win swap file and Photoshop's. But with the near instant speed of an SSD, would I be wrong in thinking that separate drives for swap files are no longer important? Specifically for HD video editing, what drive setup would you recommend without going to overkill?

But SSD's are quite a bit slower at writing than standard HDD's, so it doesn't seem like a good idea, to me at least.
What type of drive interface are you looking at for video editing (SAS or SATA)? Also, are you looking for pure performance or large capacity as well?

 

[micheljq]

For when the flash drives for desktops?

 

[gwolfman]

For when the flash drives for desktops?

What what what?

 

[mgr]

gwolfman, you say, "But SSD's are quite a bit slower at writing than standard HDD's, so it doesn't seem like a good idea, to me at least.
What type of drive interface are you looking at for video editing (SAS or SATA)? Also, are you looking for pure performance or large capacity as well?" (I don't know how to use the forum's quote feature yet...gunna go read up after this message.)

Have I misread about the write speed of SSDs, that they are only slower in situations of continuously repeated write requests in such programs as databases but not in situations with single writes with even small delays between them? Not having done any HD video editing, I'm not familiar with how the apps write to disk, but are you sure the "slow write" issue with SSDs would be a problem there?

I don't know enough yet to answer your question about SAS(?)-vs-SATA, but for HD video editing I suspect I'll be wanting both reasonably large capacity as well as performance. A conventional disk would be fine for storage, but I'm wondering about one or a RAID-0 pair of SSDs as a "work disk" in addition to a RAID-0 pair for drive C:. But I don't know enough yet to make informed decisions about this.

 

[gwolfman]

gwolfman, you say, "But SSD's are quite a bit slower at writing than standard HDD's, so it doesn't seem like a good idea, to me at least.
What type of drive interface are you looking at for video editing (SAS or SATA)? Also, are you looking for pure performance or large capacity as well?" (I don't know how to use the forum's quote feature yet...gunna go read up after this message.)

Have I misread about the write speed of SSDs, that they are only slower in situations of continuously repeated write requests in such programs as databases but not in situations with single writes with even small delays between them? Not having done any HD video editing, I'm not familiar with how the apps write to disk, but are you sure the "slow write" issue with SSDs would be a problem there?

I don't know enough yet to answer your question about SAS(?)-vs-SATA, but for HD video editing I suspect I'll be wanting both reasonably large capacity as well as performance. A conventional disk would be fine for storage, but I'm wondering about one or a RAID-0 pair of SSDs as a "work disk" in addition to a RAID-0 pair for drive C:. But I don't know enough yet to make informed decisions about this.

http://www.tomshardware.com/2007/08/13/flash_based_hard_drives_cometh/page8.html#write_transfer_performance
The write speed of one of the SanDisk SSD's is about 1/2 of what you get for a good 3.5" drive. Two of them in RAID 0 would be about equal to the write speed of one good 3.5" drive. If you can afford two of these, then your amazing read speeds would outweigh the slower write speeds. The slow writing reference I mentioned above is related to where your swap file for the OS and editing program would be (that's where my concern was).



SATA = Serial ATA
SAS = Serial Attached SCSI

Basically the SAS connectors look just like a SATA connector but it's capable of running a modified version of the SATA protocol that allows a significant improvement in data transfers. The drives have faster spindle speeds of 10,000 and 15,000 RPM's instead of the usual 7,200 that desktop HDD's have. This allows for greater performance compared to a regular SATA desktop HDD. The trade off for the improved performance is you would need to purchase a SAS controller, lower capacity drives, and a higher cost per gigabyte. That's why I asked if you wanted high performance or large capacity because there is a big difference there between the two technologies.

http://www23.tomshardware.com/storage.html?modelx=33&model1=850&model2=829&chart=37
The link above is from Toms's HDD charts. Both SATA drives offer good read/write performance and offer 750GB or 1000GB. You might also want to look at the new Seagate 7200.11 SATA drives that are coming out soon, they are supposed to have really good read/write performance. Quote: "Speedy performance at 105Mb/s sustained data rate" http://www.seagate.com/www/en-us/products/desktops/barracuda_hard_drives/barracuda_7200.11/

Does that help any?
-GWolfman

 

[ElKeeed]

What program is EWF?

EWF is Enhanced write filter. Its part of windows embedded that lets you save disk writes to ram and then write them all out at once or forget them entirely when you turn off. You can move the files across to regular XP or theres a program available that does the same thing but I'm not sure what that is called.

 

[mgr]

Gwolfman, you say...

"http://www.tomshardware.com/2007/0 [...] erformance
The write speed of one of the SanDisk SSD's is about 1/2 of what you get for a good 3.5" drive. Two of them in RAID 0 would be about equal to the write speed of one good 3.5" drive. If you can afford two of these, then your amazing read speeds would outweigh the slower write speeds. The slow writing reference I mentioned above is related to where your swap file for the OS and editing program would be (that's where my concern was)."

But when I look at the chart, the Average and the Maximum write speeds are much faster than the fastest hard drive in the list, no?

In the Conclusion of the review, the writer says...

"Multiple random write access, as required in our database and fileserver, reveals the Achilles heel of the SSD 5000: Writing to lots of different cells slows the SSD down so much that even conventional 2.5" hard drives offer better I/O and file-write performance."

But do the slow speeds that apply to database writes, also apply to conventional writes...or to the writes of the OS swapfile? The review seems to say (to my uneducated ear) that normal write speeds with the SSD are much faster than conventional drives...so I must be missing something.

Thanks for explaining what the SAS drives are and for the advice about the new Seagates.

 

[gwolfman]

But when I look at the chart, the Average and the Maximum write speeds are much faster than the fastest hard drive in the list, no?

Thanks for explaining what the SAS drives are and for the advice about the new Seagates.

That's compared to 2.5" (laptop) drives in the chart (if my memory serves me correctly), not the conventional 3.5" desktop drives. So if you'll be doing your editing on a laptop, then yeah, but why buy slower 2.5" drives (excluding SSD's) for a desktop when you can fit standard, faster performing 3.5" drives in a desktop.

And no problem about the explanation. I think those Seagates should be out within a month or so.

-GWolfman

 

[gwolfman]

But when I look at the chart, the Average and the Maximum write speeds are much faster than the fastest hard drive in the list, no?

I just found this in the article:

Quote: Using two SanDisk SSD 5000 drives for a RAID 0 configuration almost doubles the read transfer rate to approximately 122 MB/s. The sequential write performance is 70-76 MB/s, which is often inferior to that of conventional hard drives.

Conventional being 3.5" hard disk drives.

 

[mgr]

I just found this in the article:

Quote: Using two SanDisk SSD 5000 drives for a RAID 0 configuration almost doubles the read transfer rate to approximately 122 MB/s. The sequential write performance is 70-76 MB/s, which is often inferior to that of conventional hard drives.

Conventional being 3.5" hard disk drives.

OK, that clears it up for me finally, thank you. Damn shame though. The idea of an SSD that reads AND writes at many times the speed of a hard disk is a nice dream. I guess a RAID-0 pair still makes sense for C:, with perhaps two fast disks for storage/swapfiles, one for the OS swap, and the other for the PShop or video editor swap, so they're not competing over the same drive. Does that sound like a best-solution-for-now?

I do appreciate your taking the extra time to get me clear on the SSD shortcomings.