Samsung's 64-GB Solid-State Drive

Anonymous Howard writes "Just a couple of weeks ago Sandisk introduced a 32-GB solid-state drive. Now Samsung has one-upped them, unveiling a 64-GB solid-state drive. They are expecting to begin shipping in the second quarter of this year. Samsung says the device can read 64 MB/s, write 45 MB/s, and uses just 0.5 W when operating (0.1 W when idle). In comparison, an 80-GB 1.8-inch hard drive reads at 15 MB/s, writes at 7 MB/s, and consumes 1.5 W when either operating or idle. No pricing yet."

Comments

Re:finally, one big enough for regular use

[FuzzyDaddy]

I could be wrong, but I do believe flash turned off stuck in storage has a fairly limited lifetime

They specify 10 years for flash memory to hold it's data, but in practice (e.g. not at the highest temperature or most extreme operating voltage) it is significantly longer. I don't know to what extent the hard drives work around bad sectors, but they probably do it for both flash drives and the traditional magnetic type.

Re:Seek time? Should be 0ms

[26199]

Well... that doesn't necessarily mean it's as fast at random access as it is at consecutive access.

Normal computer RAM is also faster at consecutive reads than random reads.

Re:Put pagefile somewhere else?

[asavage]

Fortunately flash fails on writing not on reading so while you can't write to sectors that have failed you can still read them.

These fair similar to 2.5" drives

[Hackeron]

If comparing these to 2.5" drives instead of 1.8" drives the advantages aren't as drastic.

* 2.5" drives consume between 0.8W to 2.5W (ok, seeking eats a lot, but during sequential read or write, they consume similar amounts), almost no power consumption when they spin down.
* 2.5" drives give 53MB/sec read and write.
* 2.5" drives are very cheap and have triple the capacity.

The solid state drives are still at an advantage, but it's not quite as large as compared to 1.8" drives.

Not the MTBF, the read-write cycles.

[DrYak]

It's not about the MTBF (the wear with age), yes you can almost indefinitely read data from you flash drive, when compared to harddrives, because there's no mechanical wear.

BUT!

The flash cells have a limited number of write cycles, which is very small compared to hard drives. If you write too much data on the same sector, the sector get very quickly broken.
If you used a flash card for swap, it won't last long at all (because some sectors get constantly written over).

To limit those damages, flash controllers use "wear level". That means that the small RISC controller that interface between the flash cells and the computer interface (ATA/CF, SD, USB, etc.) dynamically remaps the sectors so the wear caused by write cycles is distributed over several different sector.
Let's say that an OS constatly writes data on the first couple of sectors. Instead of always writing on the first few cell, the controller remaps a different physical flash cell, to the logical disc sector seen by the OS.
This works as a charm for flash media storing files likes used in digital cameras and such.

But doesn't perform as well when used by an operating system.
Windows XP is specially bad at this.
Other OS - such as Linux or *BSD, that already have good support for running on slow read-only media (LiveCDs) for a long time, that don't need writing that much (except /var and /tmp, most of the rest of the installation can be read-only), and that support special file systems designed for lower wear (JFFS and such), may fare better : for example there are some Linux distribution that are tested for running from flash, like Damn Small Linux.