Recent thread on solid state disk drives

What is the advantage of these drives over, say, a 32 GB jump drive at $70 (this week at Office Depot)? Speed? If so, how great is that advantage in practice?

-- Best -- Terry

They replace the hard drive in a computer. Someone was asking about small hard drives for machine tools. Spinning storage with an IDE/PATA interface is disappearing from the market. What good is a jump drive on something with no USB port?

We have that problem at work. Our newer Mitsubishi LASER CNC control runs on Win95. The only network option is a PCMCIA reader and LAN card in the reader. We installed the hardware and got the control to recognize a laptop running Win2KPro, and vice versa, but so far, we haven't gotten drive access to allow us to transfer files back and forth.

David

The first one linked uses a combination of flash NAND memory along with a 64MB dynamic memory cache. Your jump drive doesn't have a cache to improve write read/write times.

Wes

-- "Additionally as a security officer, I carry a gun to protect government officials but my life isn't worth protecting at home in their eyes." Dick Anthony Heller

These are a huge improvement over the old 28 pin 'M-Drive' we used to run embedded NT in one product about 10 years ago. They are a lot larger, too. They were $380 for a 32 MB soft drive.

If your CNC will run with one of the formats that Windows can use, you can format the solid state drive & install the software, then just plug it into the CNC machine. You could even make a duplicate drive to use for troubleshooting or emergency repairs. It's cheap production insurance at those prices.

These SSDs do wonders for old, memory constrained computers. I installed one in a laptop with 256 MB of memory and the effect was tremendous.

They are the future for everything besides slow file storage (like movies and backups).

Right now we'd be happy if we could load files from anything other than the failing floppy drive. The control has a db25 serial port, but for some reason, Mitsubishi decided that just being able to transfer files with a COM program shouldn't work.

David

There are solid state replacements for 3.5" floppy drives, but they aren't cheap. They allow you to use a USB memory stick to load programs or data in CNC machines and other, old computers & computer based systems.

What type, brand & model floppy drive are you using? There may be a replacement, or if it is an older, full height 3.5" a good clean & lube of the bearings in the disk elevator may fix your problems. I used to repair 3.5" floppy drives when they cost >$75. Dry bearings and missing springs were common. Drives with bad heads gave me a good supply of donor parts.

If it is an oddball drive, photos would help. I currently have a couple hundred used floppy drives on hand. They are leftovers from a closed computer business, and others were removed from scrapped computer systems.

How is the seek and retrieve time on the solid state drives, as compared to the good spinning disks?

Gunner

They are smokin' fast (though some are faster than others), They actually can use up the bandwith in a SATAII connection, on sustained reads & writes, which rotating devices can only do on bursts.

In practice, well that depends on what you are practicing. If you are sending G-Codes to a machine tool. There's probably no practical speed advantage. If you are crunching through tons of database tables, there's a huge advantage.

As always, you pays your money and you takes your choice.

There is no moving mechanical mass in a solid state drive so it's a lot faster that conventional drives. there is no oxide to shed from the spinning media, and they don't mind vibration or suffer from mechanical shock like older drives. You've seen the TV ads for laptops that survive being dropped while on? Guess how they do it. :)

But the flash cells have a finite life as in write cycles.

Sophisticated wear leveling algorithms try to keep the wear spread across the cells.

The technology is improving but it isn't at a price point to drop spinning metal platters yet. My pile of drives that have failed or were recovered and no longer trusted is getting pretty darn big.

Then there is the issue that a CDROM or DVDROM doesn't have an archival lifespan. I fear a whole lot of digital content is going to die faster that content produced only

Wes

-- "Additionally as a security officer, I carry a gun to protect government officials but my life isn't worth protecting at home in their eyes." Dick Anthony Heller

It was well over 100,000 write cycles the last time i worked with solid state drives. Since the drive in a machine tool is mostly a read device, it should outlast the tool. NASA had no problem with the expected life span in 2000.

Would you rather use a solid state drive in a machine, or look for a used mechanical IDE/PATA drive that might still work while the machine is down, and nothing is being shipped? Some interfaces won't work with the newer drives, because the block size is too large on 300 GB and up hard drives. from what I've heard, there are no new IDE/PATA drives being built, and what is for sale is the last in the pipeline.

metal platters

It will continue to grow, because the higher the density, the easier it is to corrupt.

lifespan. I fear

only 50 years

Critical data should be refreshed every five years to new media, just to be safe.

"Michael A. Terrell" wrote in news:ANKdnaBrMuNLTZbRnZ2dnUVZ snipped-for-privacy@earthlink.com:

I would never use flash based memory devices for primary storage. They are fine for moving files around on USB thumb drives, but they are inherently unreliable. Flash drives wear out, and have internal algorithms to spread the wear around. I know a number of folks who've had thumb drives die on them. I realize that they have been improving, but until I see some serious unbiased tests on long term reliability, I'm sticking with spinning things. I think conventional hard drives are also less likely to get flipped bits from cosmic rays, although with adequate encoding, that _shouldn't_ be a problem.

Doug White

It depends on the OS. Unix variants (unless the filesystem is mounted read-only) update the last-accessed time in the inode for each file every time you read it. And there are a number of file inodes sharing the same 512 byte block, so the number of write cycles in an active directory would accumulate rather faster than you might expect.

This could at least be a problem with EMC (which is linux based)

-- unless care is taken to mount the SS drive read-only, and keep some other form of medium for read-write. Perhaps set it up using the SS disk something like a liveCD, and copying it into a RAM-DISK for normal execution, and only remounting it read-write when you absolutely need to write something to it.

With the Microsoft FAT filesystem, I don't think that there is any equivalent last-accessed time, but I don't know what other gotchas might be present.

Making me happy to use SCSI and FC disks. :-) At least Sun doesn't seem to have any hardware-set limits on those. :-)

That can help -- somewhat.

metal platters

:-)

lifespan. I fear

only 50 years

Yes -- now all you need is the time to keep a growing stack of CD-ROM and DVD-ROM safety copies up to date. :-)

Enjoy, DoN.

Thumb drives suffer mechanical stress, ESD and connector wear. Since you can't see the PC board, they aren't that careful with the reflow soldering. The ones I've opened were trash when they were shipped. They used lead free solder and either too low of a reflow temperature, of the flux was no good. Some of them are so bad that you can pop the chip off the board with a fingernail. Of course, the OEM consider them as expendable media. They keep doubling the capacity, and want you to throw away what you're using to buy a new one.

NASA has no problem with them in orbit. If you don't want to use them, then you better stock up now. IDE/PATA drives are a rapidly dying breed of data storage devices.

There is more analog, low level electronics in a spinning drive. The spinning drive's PC board is larger, which makes for a larger topic for stray particles. Use whatever you want. I want three of the SS drives to put in an old Dell Poweredge 4350 server.

metal platters

lifespan. I fear

only 50 years

They make autoloaders for tape drives, and I've seen them for 5.25" &

Personally, I only need to create a CD or two a month. You could copy the whole year's worth in a couple hours by hand. For me it would be no problem. I would just turn on my spare computer and let it work while I did something else at my workbench. :)

In Linux, there is a mount option "noatime" that disables that behavior.

This is not a big problem, one is because it does not result in that much writes, and also because of availabiilty of noatime.

This is a possibility, we're already using flash drives to load programs to our newer Mazak, but I'd rather get everything networked.

It looks like a standard half height 3.5" floppy drive, but it isn't. I've tried substituting new drives, but the control doesn't read them, so Mitsubishi seems to have monkeyed with them so they can charge $700+ for them.

David