SSD's - How They Work Plus Tips

[Tinman57]

[  Good article on SSD's...  Tells how they work and what to look for in a SSD, plus usage tips.....]

The proper care and feeding of SSD storage

05.13.2013 3:02 AM

Treat a solid-state drive like its mechanical cousin and you could end up in a world of pain. Here's how to handle these exotic beasts.

http://www.pcworld.c...eedy-drives-hum.html

[eleman]

I have 5 tips to add:

1. Move the tmp folder to a hard disk. You shouldn't use your valuable write cycles for temporary files.

2. Move (if you must have one) the page file to a hard disk. I have 4 gigs of ram on my win7, I sometimes get the insufficient memory notification when firefox leaks too profusely and I try to play world of tanks at the same time. With 8 gigs you wouldn't see even that one. So page files are mostly redundant if your specific needs (using photoshop to prepare 10m x 24m banner prints etc.) don't dictate it, get rid of the page file. But if you must have, move it to a hard disk.

3. Move firefox (or ie, or chrome, whatever) cache to a hard disk. Yes this will make it somewhat slower, but your SSD's write cycles would be spared. If the speed penalty is too much, disable on-disk caching completely. On-memory caching will probably do (it does for me).

4. If you use a mail client such as outlook, thunderbird, bat, eudora etc., move the mail storage to a hard disk. Yes, it will degrade performance, especially when you need to search among thousands of mails, but it will help the longevity of the SSD.

5. If you have a busy database running on your computer (you may not even be aware of it. For instance I use Trados, a computer assisted translation tool, and it runs on top of a database.) you may consider moving it to a hard disk. The performance hit will be immense (depending on your usage pattern) though. I don't use this trick personally. I would not want to waste 10-20 minutes a day just to extend the life of a $80 SSD drive by 10%. But if you can bear the performance hit, you can extend the life of the drive.

[Stoic Joker]

SSDs, and solid-state storage in general, have a disturbing tendency toward binary functionality.

-The Article

A disturbing tendency towards binary functional... LOL ...We used to just call that "light-bulbing" ...Nice to know they have a fancy new name for it now.

Until there is a recovery option that I can do myself I'll be sticking with the (good) "old fashion" mechanical drives.

[f0dder]

I stopped reading the article at

With hard drives, the faster the spindle speed, the faster the drive. The amount of cache also comes into play, but by and large, a 10,000-rpm drive is faster than a 7200-rpm drive, which is in turn faster than 5400-rpm and 4800-rpm drives. That’s an easy and intuitive metric for comparison shopping.

..if they get something as simple as that wrong, I don't want to waste my time reading the rest.

[mouser]

f0dder can you elaborate -- that sounds like a reasonable statement to me -- though i am an admitted newbie when it comes to hardware.

[Stoic Joker]

that sounds like a reasonable statement to me

-mouser (May 14, 2013, 12:47 PM)

Me too ... But I'm not a hardware guy either. I was under the impression that (seek time being roughly fixed) latency was reduced by the higher spindle rates...which resulted in faster access times.

[phitsc]

There was quite a good intro to how SSDs work in Communications of the ACM recently called 'Anatomy of a Solid-State Drive'. While in my memory the article looked nicer (i.e. nicer layout), I think the contents is identical to this one:

http://queue.acm.org...etail.cfm?id=2385276

[40hz]

f0dder can you elaborate -- that sounds like a reasonable statement to me -- though i am an admitted newbie when it comes to hardware.

-mouser (May 14, 2013, 12:47 PM)

that sounds like a reasonable statement to me

-mouser (May 14, 2013, 12:47 PM)

Me too ... But I'm not a hardware guy either. I was under the impression that (seek time being roughly fixed) latency was reduced by the higher spindle rates...which resulted in faster access times.

-Stoic Joker (May 14, 2013, 02:40 PM)

It's not so much he's wrong about 10,000 RPM being faster than 5400RPM - depending on what is meant by "faster.". But it's a mistake to simply equate raw spindle speed and cache size with disk performance, which is what he seems to be implying.

Partitioning, I/O  distribution on the disk, I/O bus width, cluster size, filesystem(s) used, and several other factors have a much more direct and measurable effect on overall performance than just the spindle speed or cache size.

Generally, the number of physical R/Ws per second and the transfer capacity in MB per second are a much more significant determinant of overall drive performance. And that is mostly achieved by the design of the controller, which is usually the single most critical part of the disk's hardware chain. And also why some slower spinning 'enterprise' drives can outperform much faster spinning 'consumer' grade desktop disks.

[f0dder]

f0dder can you elaborate -- that sounds like a reasonable statement to me -- though i am an admitted newbie when it comes to hardware.

-mouser (May 14, 2013, 12:47 PM)

Platter data density.

What will deliver the highest throughput - "something" at 7200rpm, or twice the data density at 5400rpm?

[wraith808]

Platter data density.

-f0dder (May 14, 2013, 03:25 PM)

Also known as Areal Density.  Old, but good article: http://www.tomshardw...dd-storage,2563.html

[mouser]

I guess a more accurate statement would be: "All other things being equal, faster spindle speeds nearly always mean better the performance."

And then adding something about what other factors have the greatest impact on real-world performance.

If you were trying to give someone some quick rules of thumb for choosing fast drives, i still say it makes sense to tell them to look for fast drives and to not be too distracted by cache sizes, and "max" throughput rates achievable by the card.  Would you agree with that? Can you formulate a simple way to tell people what to prefer in terms of density/plattercount?

Or maybe you think the best thing to do is to tell people to ignore all such stats and find a site that will compare drive performance explicitly for the drive you are considering purchasing.

ps.
As someone who has become paranoid about drive temperatures (in terms of fearing a hardware failure due to overheating) -- i tend to focus FIRST not on speed but on reported drive temperatures.. If I find a HD with great performance but which the reviews say runs hot, i run away.

[Jibz]

Perhaps you are expecting too much technical accuracy from a side argument in a consumer article in a consumer magazine .

Personally, I find the title more misleading -- "proper care and feeding" basically boils down to "it takes care of itself, just buy a big one".

[40hz]

A quick rule of thumb without getting too technical?

General best performance = SSD

Best current $/capacity ratio = standard HD

Pick your trade-off point. (Too soon to tell if those hybrid drives will eventually hit the sweet spot.)

[Stoic Joker]

that sounds like a reasonable statement to me

-mouser (May 14, 2013, 12:47 PM)

Me too ... But I'm not a hardware guy either. I was under the impression that (seek time being roughly fixed) latency was reduced by the higher spindle rates...which resulted in faster access times.

-Stoic Joker (May 14, 2013, 02:40 PM)

It's not so much he's wrong about 10,000 RPM being faster than 5400RPM - depending on what is meant by "faster.". But it's a mistake to simply equate raw spindle speed and cache size with disk performance, which is what he seems to be implying.

-40hz (May 14, 2013, 03:14 PM)

Seems like it's more a case of what the crew is inferring...

Partitioning, I/O  distribution on the disk, I/O bus width, cluster size, filesystem(s) used, and several other factors have a much more direct and measurable effect on overall performance than just the spindle speed or cache size.

-40hz (May 14, 2013, 03:14 PM)

...Yes, but these are all factors that are external to the central moving parts vs. non moving parts theme. As these are all factors that could effect either design by a users bad install, or by using a cheap MBoard.

If as mouser eludes all other possible random factors are fixed as accepted equals, and the distinction is narrowed to pro/con of moving vs. non moving designs ... In that context is makes sense. But then again I like the lower speed drives because the bearings last longer if they spin slower, and I've gotten stuck arguing with some sales-tard at BestBuy enough times that persisted in pushing the issue that the 7200+ RPM drives would be faster that I'd have to assert that it is a rather popular (miss)conception..

[40hz]

...Yes, but these are all factors that are external to the central moving parts vs. non moving parts theme. As these are all factors that could effect either design by a users bad install, or by using a cheap MBoard.

If as mouser eludes all other possible random factors are fixed as accepted equals, and the distinction is narrowed to pro/con of moving vs. non moving designs ... In that context is makes sense.

-Stoic Joker (May 14, 2013, 05:52 PM)

Agree, but only up to a point since it's generally pointless to argue about specifications outside of the environment they're being applied to. Computers are systems, so there's no such thing really as something that exists in complete isolation as purely hardware or software. Every system incorporates both. And it's a balancing act as we all know too well.

But my professional activities deal mostly with "real world" performance issues. So I'm somewhat biased against absolute specs and biased towards practical suggestions and recommendations. And that usually means not reading too much into published specs or artificial test results.
 

[Tinman57]

  No matter how you look at it, SSD's have a higher failure rate than hard drives, and until they get that problem fixed, I'll be sticking with my 7200 RPM drive......

[Stoic Joker]

  No matter how you look at it, SSD's have a higher failure rate than hard drives, and until they get that problem fixed, I'll be sticking with my 7200 RPM drive......

-Tinman57 (May 14, 2013, 08:52 PM)

Amen to that!


@40hz - I hear ya man, I spent an absolutely insane amount of time agonizing over which way to do the arrays (IOPS...) on the new Hyper-V Data Center. Yes every time I called (HP) the distributer's support line I got a different guy with a different school of thought as I diced between RAID5 vs. 10 (I was trying to get away from 5 due to previous discussions - Yet nobody agreed). I ended up with dual 8 disc hot-swap controllers; mirrored set of 15,000RPM SAS drives for the host OS, and the guests all sit on an 8 disk 7200RPM Nearline SATA RAID 5 array. The system is stunningly fast, and I haven't seen the thread queue even get to 1 yet with 12 systems running on it.

[40hz]

I ended up with dual 8 disc hot-swap controllers; mirrored set of 15,000RPM SAS drives for the host OS, and the guests all sit on an 8 disk 7200RPM Nearline SATA RAID 5 array.

-Stoic Joker (May 14, 2013, 10:31 PM)

Awesome! Muy macho...I like.

The system is stunningly fast, and I haven't seen the thread queue even get to 1 yet with 12 systems running on it.

Stunningly fast? Yeah...ya think?

Like I said: awesome.

[40hz]

  No matter how you look at it, SSD's have a higher failure rate than hard drives, and until they get that problem fixed, I'll be sticking with my 7200 RPM drive......

-Tinman57 (May 14, 2013, 08:52 PM)

Yeah. There is that little problem...

Probably the main reason why I still shy away from them unless a client insists on getting one.

If they do opt for an SSD however, I'll always set up a chron job to image of the SSD over to a standard hard drive at least once every 24 hours. With 1-2TB SATA drive sizes, imaging the SSD system drive hardly puts a dent on the available disk space.

This way, when the fancy SSD ultimately shuffles off to Buffalo, all it takes is a drive swap, a boot from a USB key or CD, a few questions answered, and the SSD owner is back in business.

Better them than me. I'll wait a bit longer before I use them in any production environment I make the decisions for. To me, the extra speed is just not worth the reliability trade-offs at this stage of the game.

Maybe next year...

[johnk]

  No matter how you look at it, SSD's have a higher failure rate than hard drives, and until they get that problem fixed, I'll be sticking with my 7200 RPM drive......

-Tinman57 (May 14, 2013, 08:52 PM)

I swapped to an SSD for my system drive about a year ago, and couldn't go back to a hard disk. The increased speed is worth it, to me. Although I used many of eleman's tips when I first installed the SSD, I recently moved my browser cache to the SSD to speed up browsing. I'm willing to take the risk of shortening the SSD's life for the speed it brings. The SSD is imaged regularly and all important data lives on hard disks.

[wraith808]

I swapped to an SSD for my system drive about a year ago, and couldn't go back to a hard disk. The increased speed is worth it, to me. Although I used many of eleman's tips when I first installed the SSD, I recently moved my browser cache to the SSD to speed up browsing. I'm willing to take the risk of shortening the SSD's life for the speed it brings. The SSD is imaged regularly and all important data lives on hard disks.

-johnk (May 28, 2013, 01:20 AM)

My main computer doesn't have an SSD, but my media computer does.  When my wife's computer died recently, she started using it full time until I replaced it.  I'm very surprised to see that with an SSD, it's only a little slower than a full sized computer.  And it's one of those book-sized computers.  It's a given that there's some things it can't do... but the SSD makes a huge difference.

[pilgrim]

When it comes to cache and temp files if you have enough memory put them on a RAM Disk, no loss of speed and if you want to save it on shutdown you can.

I use Dataram RAMDisk on all my computers, on Windows 7 it's set to 4GB and holds all the cache and temp files for both 7 and XP Mode.
I also use it to temporarily install to if I just want to check out any software or get a product key.

I keep an image file with just the empty folders I use, save the image to a normal hard drive and it reloads at startup.

[Mark0]

In my (admittely not very long) experience with SSDs, I actually never met one made inoperable due to flash wear, while I have seen various briked by faulty electronic / controller or simply bad firmware (or after an update of the latter).
So, I think the most important thing is to do the proper homeworks before buying, and getting a model with a good track record. I have good experiences with Samsung (I never heard of serious firmware problems with the 830 serie, for example). Probably the fact that they do the entire thing in house by themselves helps.

[johnk]

When it comes to cache and temp files if you have enough memory put them on a RAM Disk, no loss of speed and if you want to save it on shutdown you can.

-pilgrim (May 28, 2013, 09:37 AM)

There have been one or two lengthy discussions here on the pros and cons of RAMdisks. Do you see significant benefits, pilgrim?

[pilgrim]

When it comes to cache and temp files if you have enough memory put them on a RAM Disk, no loss of speed and if you want to save it on shutdown you can.

-pilgrim (May 28, 2013, 09:37 AM)

There have been one or two lengthy discussions here on the pros and cons of RAMdisks. Do you see significant benefits, pilgrim?

-johnk (May 28, 2013, 11:24 PM)

As I commented elsewhere I never benchmark anything so my answer/opinion is entirely subjective.

Compared to my newest PC both my XP computers are slow, the Netbook has an N270 (OC'd to 1.74Ghz), the PC a 3.066Ghz P4, both are limited to 2GB of RAM which in turn limits the size of RAMDisk I can use.
One of the first things I moved was the Firefox cache and in my opinion that definitely improved things on both computers, for other things I would say that there was an improvement but by how much is debatable.

On my newest PC I have 16GB of RAM, most of the time my normal usage rarely exceeds half that so a 4GB RAMDrive is not a problem, I do not have a Page File.
Because of the overall specifications of the machine and the fact that the system drive is an SSD any advantages in terms of performance are probably minimal.
Having said that, it keeps the cache and temp files off of the SSD and it is faster than it would be if I had moved them to a hard drive.
Also, as I said in my previous post I use it for other things.

The bottom line: As long as I had the resources in terms of available RAM I would always use a RAMDisk.
Would I recommend them to others? Subject to the same criteria yes, there is something to gain and as far as I can see nothing to lose.
I am only aware of one thing that some might consider a negative and that is if you save a RAMDisk image that has a lot of files on it, it will increase your start-up times, by how much depends on the files involved and the system itself.
That's one of the reasons my image contains just a few empty folders, if I am about to shut down and want to save anything else I simply copy it to a hard drive.

Open at your own risk!

I was surprised at the reservations expressed about SSD's in this thread.
I know that to start with there were problems with some of them.
But unless I am mistaken I'm sure I read something recently that said SSD's can be cured?