Folding Forum

What is the reliability of those drives? Flash is prone to break.

Ivoshiee wrote:What is the reliability of those drives? Flash is prone to break.

That's actually superstition. A modern flash device will have wear-out time measured in decades, with a much better random MTBF due to having no moving parts. Work out how long it would take in 100% write duty cycle to fill the disk enough times over to reach the write cycle limit.

Ivoshiee,
Read this very good article about those SSD-s
http://www.anandtech.com/cpuchipsets/in ... spx?i=3403
After that i have no doubt that SSD-s are more reliable and future proof. Those drives are going to follow Moore's Law.

Having a SSD will have no effect on your F@H output.

shatteredsilicon wrote:A modern flash device will have wear-out time measured in decades

FYI, data retention times on Flash ROM chips are often quoted on data sheets as 10 years. Given the prices of these things, I'd want something that would last more than twice as long as the typical hard drive.

The markup you're paying is for speed (sub-100us access time), shock-resistance, and reduce power consumption not for data retention longevity.

It also depend on what you're comparing them with in terms of price. Purely on size, it's about 22.5x more expensive compared to optimally priced 7200rpm SATA disks. You'll find the price-gap rapidly closes when you go up to 10Krpm disks (e.g. WD Velociraptors) and almost disappears with 15Krpm SAS drives (e.g. latest Seagate Barracudas). And a 15krpm disk will still have 3+ms access time compared to SSDs sub-100us.

Of course, for optimum performance, you'll probably want something like this:
Flash+battery backed SATA2 RAM disk
But I doubt you'll get much change out of $700 for a 16GB setup.

It really comes down to access time. Do you really need it under 8ms? If it's only bandwidth that's important, half a dozen cheap SATA disks will probably do just fine.

Im using CF-IDE in my dedicated folding computers, no need for SSD or harddrives. CF is also well proven under harsh conditions.

Compact flash pros:
- Cheap
- Small even with the IDE adapter
- Robust (proffesional cameras use these outdoors)
- Very mature technology
- IDE (no extra drivers needed)
- Simple and fast enough (30/30+)

No need for SSD in my opinion.

It's not more RAM you need for folding (unless your machine is swapping all the time), it's faster RAM I/O. F@H seems to be very RAM I/O bound. So, bizzarely, a faster processor (e.g. Core2) won't necessarily do as well as one with higher memory bandwidth due to an integrated MCH (Athlon/Phenom).

shatteredsilicon wrote:Having a SSD will have no effect on your F@H output.

That's right.
If silicon drives were to save 10 milliseconds per checkpoint write, then that would amount to about 6 minutes extra folding time per year in a dedicated machine.

Still, it's great to see solid state drives in the market. Another wish fulfilled...

Adam A. Wanderer wrote:Yes, anything that reduces crashes, lost data and so forth is appreciated. Moving parts are still a "weak link" in any system.

You're telling me. I had a RAID1 stripe fail in my machine. Both disks went within minutes of each other. I just spent a day rebuilding the box to PXE/NFSRoot while the disks get RMA-ed. Didn't lose any data (mirrored additionally to another server), but OMG was this annoying. I was amazed by the consistency - both disks failed with massive media errors, in similar regions on both disks. Must be a systematic manufacturing fault with that batch (they were consecutive serial numbers). This has got me seriously thinking about going SSD, but having said that, these failed disks were only 7 months old (3 year warranty).

As a consequence, my PPD production has been quite firmly at zero for a few days.

Well since even nuclear plants use the oldest industrial techengine we have to make power(steamengine) I guess its far stretched.