Flash based HDDs

JonWitte · 24th August 2007

Ok, so Segate are going to start shipping 160GB flash based drives next year. Can see these Babies being great in servers (Power, access time etc.), but would you bother RAIDing them? Most of the drive failures we've had are mechanical, although we've lost a couple to power spikes that blew the controller board.

Thoughts?

philb · 24th August 2007

Throughput is generally poor on the current generation of flash based devices, and the cost of these boxes (which as yet are laptop focused) makes 2.5" SAS look cheap. :P

othellotech · 24th August 2007

Just took delivery of 4 1Tb Sata drives - you can keep your CF's

edb49 · 24th August 2007

Jon,

Considering the target market, I'd imagine 99% of people buying these for server use will RAID them.

JamesSykes · 3rd September 2007

I would always use RAID. I dont care if its flash based or not, everything is prone to failure.

I cant see these things replacing traditional hard-drives in servers for some time. Would be nice to have a raid 1 flash based and a standard raid5 for your big storage.

BurtyB · 3rd September 2007

Anyone seen any large ones for sale? I was having a look the other day and Dabs had a 30GB one but that was about the biggest I could see without emailing for prices.

ChrisB.

Cyberprog · 3rd September 2007

Presumably they've got round the read/write limitations on flash chips then?

BurtyB · 3rd September 2007

Quote:

Originally Posted by Cyberprog

Presumably they've got round the read/write limitations on flash chips then?

From what I've read about them they use some form of logic in front to spread the write operations over all chips and/or have spare memory to take over high write areas.

ChrisB.

Cyberprog · 3rd September 2007

I see. Wonder what happens when it goes kaput though, can data recovery people get it back?

Schumie · 3rd September 2007

Generally, when I've heard of these larger drives going bad, it's near impossible to recover. However, as I've never had to have one recovered I can only say what I've been told by others. We'll be sticking to SAS's for the moment in the SAN.

Karl · 4th September 2007

From what I've read, new flash memory has a lower error rate than traditional magnetic drives now - Each sector can cope with the equivelant of about 10 years worth of disk writes (in an average situation) I seem to recall. As for keeping some spare to cover up for bad sectors, that's exactly what hard disks do - when you start seeing bad sectors, you throw it away, because it's already had thousands of them and used up it's spare to mask them from you.

JamesSykes · 5th September 2007

What Karl said, they can now do alot more read/writes than older flash memory. That said there is still a limit however i believe they get around this partially by spreading data across the drive as much as possible to reduce the possibility of a sector going bad from over use. I think i remember reading they are also clever in that they count the number of transactions and just mark them dead when they reach a limit.

Anyway i think they are probably good enough to use in most scenarios, just dont expect it to keep going like some ageing 10 year old P200 that you still have in the corner somewhere running your DNS

JonWitte · 19th September 2007

Intel getting on the bandwagon now. Talking about 10X to 50X increase over traditional media, although can't seem to find out what interface they're launching with...