Posts Tagged ‘storage’

SSDs: are you experienced?

Kingston SSDNow V-Series 128GB[tweetmeme source=”KeithBluestone” only_single=false]First reaction after installing an Kingston SSDNow V-Series 128GB SSD boot drive in my custom-built Core i7-860 PC running Windows 7:  awesome.

While several times the cost per GB of conventional drives, an entry-level SSD will run many times faster, and I think  it’s the perfect companion for today’s high-end processors.  The days of using conventional boot drives are surely limited.

I noticed that there are a lot of sites pirating this article verbatim.  Here is a link to the original on SoftwareKeith.com… — Keith

Fast. Smooth. Quiet.

The SSD at US$250 (on NewEgg.com) was rather pricey for a single PC component — it cost as much as the Core i7-860 CPU itself.   But I knew almost immediately that it was the right decision: with the SSD installed, everything flies !  The system feels so “smooth,” like the hard drive and the processor are in sync.  Windows 7 Ultimate installed in about 10 minutes flat;  it boots in about 20 seconds.   Apps leap onto the screen again within a second or two.

My favorite readers will remember that after my very fast RAID-10 array died (see my last post), I had to run the Core i7 box off a single 7200 RPM drive for a while, which showed clearly that the hard drive was a performance bottleneck.

Formatted, the SSD has about 120GB of space.  After installing Windows 7 Ultimate and a handful of core applications (FireFox, Picasa, Windows Live Writer, etc.), I still had over 90 GB free.   After some heavier installs – including Office Professional 2010, Microsoft Visual Studio 2010, and Microsoft Visual Studio 2008 – there’s still well over 80 GB free.  That’s more than enough for most people to play with for quite some time.

Why SSD’s smoke conventional drives

imageIn a word (or two): access time.  The access time is how long it takes the storage device to read data.

For conventional drives, this involves waiting until the data on the spinning hard drive platter (right) rotates under the read head, positioning the read head arm to the correct track (radially), and reading the data from the platter.  Conventional desktop hard drives, even the best in the world, have access times of  4 to 8 milliseconds, which turns out to be an eternity for today’s processors.

The following analogy brings home the massive disparity between the speed of a modern processors and hard drives:

The first thing that jumps out is how absurdly fast our processors are…  reading from L1 cache is like grabbing a piece of paper from your desk (3 seconds), L2 cache is picking up a book from a nearby shelf (14 seconds), and main system memory is taking a 4-minute walk down the hall to buy a Twix bar.  Waiting for a hard drive seek is like leaving the building to roam the earth for one year and three months.
— “What Your Computer Does While You Wait,” Gustavo Duarte

As it turns out, most of the work done by an operating system involves reading a ton of little files, more or less “randomly” accessing the hard drive.   Thus, impressively fast sequential read or write speeds are not nearly as important as random access read speed.   Anand Lal Shimpi explains why, even though the cost per GB is so much higher, SSDs are worth it:

Measuring random access is very important because that’s what generally happens when you go to run an application while doing other things on your computer. It’s random access that feels the slowest on your machine.  Most hard drives will take closer to 8 or 9 ms in this test.  The fastest SSDs can find the data you’re looking for in around 0.1 ms. That’s an order of magnitude faster than the fastest hard drive on the market today.  [KB: it’s actually almost two orders of magnitude faster…]
— “The SSD Anthology: Why You Should Want an SSD,” AnandTech, March 2009

This explains my own experience:  even though my formerly alive RAID-10 array benchmarked faster than the Kingston SSD overall, with a PassMark Disk Mark score of 1100 to the SSD’s 950, the system feels so much quicker with the SSD – without the headaches of RAID-10.

This is why I’m now an SSD convert.

See with your own eyes

Watch the actual launch speed of a handful of common applications on my Core i7-860 below.  This screencast was done immediately after reboot, so no applications are pre-loaded or cached in memory.  Most apps load in about a second or so;  Outlook 2010 takes the longest, but since my mail archives are on a network share, the five or so seconds it takes to load includes accessing a remote filesystem.

Windows 7 Ultimate + Core i7-860 @ 3.3 GHz + Kingston V-Series SSD

Conclusion

The lowly old spinning-platter hard drive is the primary bottleneck in the modern computer.   Though pricey, an SSD is a perfect match for a today’s fast processors.

***

For those still reading…

Benchmarks are below – you can skip this section if you’re not interested in my technological prognostications.

I’ll make a bold prediction: as a boot drive, the SSD was so effective at speeding up my computer, I believe that within two years, they will become mainstream as boot drive choices.  With the ever-increasing capabilities of our processors, and the ever-increasing demands we put on our computers, it’s a perfect choice.

The default configuration would be be an SSD- or memory-based boot drive, on which the operating system and applications are installed, supplemented where necessary by a second, higher-capcacity legacy technology drive (you know, the ones that go ‘round and ‘round).

Intelligent OS storage architectures?

If we’re lucky, Microsoft will get inspired and allow seamless stitching of fast SSD and slow legacy storage in their next version of Windows.  This not-yet-invented technology would enable two drives – a fast, smaller SSD and a slower, larger conventional drive –  to be seen as a single logical storage partition. The OS would have the intelligence, for instance, to automatically install applications on the fast part and keep things like large images – when necessary – on the slower drive.  Why not?

imageWhile you’re at it, Microsoft: use that legacy hard drive for a completely automated, idiot-proof backup system. This would have one switch at the highest level: “back up my system” – or not.   Want to improve your “street cred” against upstarts Apple and Google?  Let no Windows user henceforth ever lose their data. It’s the right thing to do.

Let’s face it: the SSD could basically be considered just a fast hard drive cache. Caching technology and cache-hit optimization strategies are fairly well-understood, as are the dynamics of logical block translation in operating systems:  why should it be difficult to have the OS manage and optimize a hybrid storage array?

It turns out there already are “hybrid hard drives” or “HHD’s”.  See the Tech Report’s “Seagate Momentus XT: a hybrid for the masses?” and  Wikipedia’s entry on hybrid drives.  These drives blend flash memory and a conventional hard drive in one package.  Unfortunately, this is not as flexible as an OS-based implementation would be.

Benchmarks

I promised benchmarks…  many of course are out there on the web, but below are some from my computer.

PassMark’s Disk Mark measured the random seek performance of the SSD at 60% higher than the RAID-10 array (in MB/s):

2010.08_PerformanceTest_Disk_Mark_-_i7-860_and_Kingston_SSD

HD Tune clocks its read performance at 250 MB/s, stellar:

2010.08_Kingston_SSD_HD_Tune_Read

HD Tune’s file benchmarks show file reads and writes many times faster than the average drive (in MB/s):

image

Windows Experience Index scores it 6.8 out of…  7.9? Could anything be less clear than Microsoft’s own explanation?

image

More Reading

As it’s mid-2010, I suppose I’m a little late to the party, but…  who’s going to be ahead of Anand?  Regardless, it’s good to be here:

“For the past several months I’ve been calling SSDs the single most noticeable upgrade you can do to your computer. … Whenever anyone mentions a more affordable SSD you always get several detractors saying that you could easily buy 2 VelociRaptors for the same price. Allow me to show you one table that should change your opinion.”
Anand Lal Shimpi, “The SSD Anthology,” March 2009

A few months later, Anand followed up this magnum opus with yet another:

“What have I gotten myself into? The SSD Anthology I wrote back in March was read over 2 million times. Microsoft linked it, Wikipedia linked it, my esteemed colleagues in the press linked it, Linus freakin Torvalds linked it. ”
Anand Lal Shimpi, “The SSD Relapse: Understanding and Choosing the Best SSD,”  August 2009

Other links:

Advertisements

Going digital: the cost of photo storage

Summary

imageStoring photos costs next to nothing. 

You can take over twelve (12) high-resolution, properly backed up digital photos for a single penny.  

For the cost of a Starbucks latte, with tip, you can take around five thousand (5,000) high-res shots.  

Snap away

So not only should you feel free to go wild taking pics – you can also go digital for next to nothing, and free yourself from reams of paper documents every year.  

What’s the catch?   You have to make sure they’re backed up, and you have to learn to use photo management software (e.g. Google’s Picasa). 

Back story

I’ve enjoyed digital photography since 2001, when I got my first digital camera, a Nikon CoolPix 950.  I loved this little camera:  it had a cool swivel-body design and felt great in my hands. 

I ended up taking 10,000 shots with it in the first year.    Nikon Coolpix 950

Since then, I have upgraded to a Canon EOS-20D (a digital SLR and a fantastic camera) and, for around-the-house and other daily subjects, a conveniently small Canon SD1100IS, also highly recommended. 

My current DSLR is a Canon EOS-20DSomewhere around 2006, with the debut of Google’s free – and extremely easy to use – Picasa photo management software, I realized that snapping a quick picture of a paper document was an easy way to preserve it.  

Instead of makingimageand filing paper copies of my company expense reports, I snapped digital pictures of them and tagged them in Picasa as “expense reports.”   

Instead of filing auto repair bills, I snapped and tagged.   And so on.

Today, the only paper documents I keep are official legal documents, such as car titles and signed non-disclosure agreements (NDAs).   The rest are on my computer’s hard drives as digital photos – backed up and archived as well. Picasa’s incremental search enables me to find any tagged photo in seconds. 

I love being paperless now.     

From time to time, I wondered about the “real” cost of all these digital photos.  It was cheap, I knew — but exactly how cheap was it?   Could I take photos at high resolutions like eight megapixels, or should I downsize to save space? 

I decided to find out.  

Figuring the storage cost of a photo

If you’re not interested in technical number-crunching related to figuring the cost of storage, you can skip to the next section.

I’m not even going to consider the cost of the electricity needed to power the camera or the computer:  it’s surely almost nothing.  (Maybe a helpful reader will do the math?)  Nor am I going to consider the cost of the camera, since that’s a personal choice.   

Hard drive detail

Instead, the cost of a digital photo is simply the cost of the hard drive space needed to store it.   Here are some conservative assumptions of the cost of disk space in a personal computer (all currencies in U.S. dollars):

Cost of 1 terabyte (1 TB = 1,000 GB) of hard drive space = $100.  
Easy to find terabyte drives at this price point or below.

Cost of 1 gigabyte (1 GB = 1,000 MB) of storage = $0.10 = one dime.   
Just ten cents per raw gigabyte!  That is amazing to me.  

Now that we know the cost of raw hard drive storage, we need to make some assumptions about the size of each photo. Then we can simply divide one into the other to get the cost per photo: 

Size of a high-resolution (8 MP) photo is five megabytes (5 MB).   
I got this figure by looking at some actual JPEG photos I took with my Canon EOS-20D.  Since JPEG is a compressed format, picture sizes will vary for different subjects, but this seems like a reasonable, conservative number.

Now we can calculate the raw storage cost of a digital photo:

Cost of a high-resolution digital photo is $0.0005 = 1/20th of a penny.
To get this, I multiplied $0.10 per GB storage cost by  0.005 GB (that’s 5 MB for a photo).  

Put another way, you can take 20 high-resolution pictures for a single penny.

So there’s our first answer: twenty photos for a penny, or an amazing two thousand photos for a dollar.   That’s insanely inexpensive!  

But hold on – as with many things, reality is just slightly more complex.  

Figuring total cost of ownership (TCO)

For a more accurate storage cost, we should really account for storing multiple copies of our pictures.    In reality, we don’t just take the photos and store them on a single hard drive;  they need to be backed up. too.   A good rule of thumb is that anything worth preserving should be saved in at least three places.  

With only a single backup (the “originals” and a backup copy), if your primary hard drive fails or is otherwise compromised (drenched, burned, stolen, etc), you have to cross your fingers and hope that your single backup copy is good.   Not pleasant.

To protect against a single hard drive failure – namely, the hard drive on which you store your precious photos, as well as a lot of other stuff – you can set up a mirrored drive configuration (RAID-1).   Everything the system writes to a mirrored hard drive, it also writes at the same time to a second hard drive (the mirror), maintaining the two as exact copies of each other.   I use RAID mirroring on all my storage drives and highly recommend it.   Unfortunately, RAID is a slightly advanced technology – you may want to ask your favorite tech buddy for help getting started with it.  

So let’s assume that for every hard drive you buy, you’ll buy at least another two for backup, mirroring, and/or archival.   

But this still isn’t completely accurate:  it models cost as if the photos were “paying for” the entire hard drive.  In reality, the hard drive is shared: with the operating system (e.g. Windows OS, Mac OS, etc.), with installed applications, and generally with a number of  other, non-photographic data like documents and databases.   (Hopefully you are backing all this up, too.)  Accordingly, if we discount the cost of the hard drive space by something reasonable like 50%, then photo storage becomes even less expensive (twice as cheap).  

With this updated and more realistic model of keeping three copies of our photos around and sharing the “cost model” of storage within the computer, we now get:

Cost per PHOTO gigabyte (1 GB = 1,000 MB) of storage = $0.05 = one nickel.   
Divide the raw storage cost of $0.10 per GB by two to discount it. 

Storage needed for a 8 MP photo is fifteen megabytes (15 MB).   
Since we always want three copies around, we multiply the photo size (5 MB) by three.

And now we can divide one into the other to find out the “real cost” per digital photo: 

“Real cost” of a persistent high-resolution digital photo is $0.00075 = ~1/12th of a penny.
To get this, I multiplied $0.05 per GB storage cost by  0.015 GB (that’s 15 MB) per photo stored in triplicate.    “Persistent” is used here in the software engineering sense of “can or will not go away easily.”

So if there’s any bad news, it’s that the real cost of a digital photo is really a little more than what we calculated initially as the “raw storage cost.”    The good news is that a little more than “incredibly small” is still incredibly small:  we can take about twelve “persistent” photos for a penny.

Life is good.

Conclusion

Any way you cut it, photo storage is super-cheap!    What does this mean in our everyday life?

We can take twelve eight-megapixel photos for a penny.    That’s twelve hundred high-resolution, doubly backed up digital photos for, oh, about a buck. 

For the price of one Starbucks grande cappuccino, dry, with tip ($4), we can take and store almost five thousand high-resolution photos.   If it’s pretty, take a picture of the cappuccino, too.   

Latte art

Five thousand photos per year is about fourteen per day, every day.   Or about one hundred photos every weekend of the year.  

Five thousand high-resolution pictures will still only consume about 25 GB of primary hard drive space.  This is only a few percent of today’s desktop drives, which are 1,000 GB  (1 TB) and rising in size. 

The incremental cost of digital pictures is almost zero.  You have already sunk big dollars into the camera, the computer, and its hard drives.   Using digital photos to capture anything now costs almost nothing, whether it’s your kid drooling on the rug or every bleedin’ piece of paper that you would have filed somewhere, only to never, ever be able to find it when you need it…. 

So snap away!   If you do decide to go digital, just make sure that you back it all up.   The only question about hard drive failure is:  when?

Six failed hard drives    Think it won’t happen?  Here’s six
of my hard drives that failed.


On digitizing documents…

Don't be like thisI’ve had flatbed scanners over the years, and although I will admit it’s been a while, I don’t like them nearly as well as digital cameras for capturing documents.  

For one, a scanner is another piece of hardware to buy and maintain.  Number two, it’s another piece of software to figure out and run when you want to scan.   Thirdly, a scanner takes up valuable desk space.   And finally, a digital camera is extremely portable and can be used anywhere to “capture” a document.

To capture a paper document with a digital camera, I simply take a picture of it, making sure to include the entire document — you can always crop it later.   I try to use a flash whenever possible to minimize movement and shadow; it also makes text sharper.  Then every so often, I transfer the images to my computer and “tag” them in Picasa (e.g. “expense report” or “financial” or “bill”) so that I can find them almost instantly in the future. 

More reading…
  • Backup Tips IOMega.com
    A good primer: “A comprehensive data backup strategy is vital to your data security. Too many people wait until disaster strikes before they think about a backup. A good backup is an excellent way to protect against viruses, deteriorating hard drives, disasters and human errors. If it would not be cost effective or even possible to re-enter data, then you need a backup strategy.
  • Introducing Picasa 3  A video tutorial by Google on YouTube
    If you don’t currently use photo management software, Picasa is an excellent, free starting point.   The install is painless – try it today at Picasa.com!
  • What’s new in Picasa 3.5  Another video tutorial from Google on YouTube
  • How to store digital photos  PhotoShelter.com
    A good look at issues, cost, capacity planning, and total cost of ownership for the beginner all the way up to professional photographers.
  • Mozy.com  
    If you’re not backing up yet, this is a cheap, free, and painless way to get started.  Mozy is very easy to use, just download the software and follow the basic instructions.
  • Digital photography Wikipedia
    "Almost all of the cost of digital photography is capital cost, meaning that the cost is for the equipment needed to store and copy the images, and once purchased requires virtually no further expense outlay.”