Brian's Brain

Jul 18 2008 1:00AM | Permalink | Email this | Comments (5) |
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It seems like just yesterday (but it was actually 1.5 years ago!) that I was first writing to you about the world's first 1 TByte 3.5" HDD. That five-platter monster from Hitachi might have been record setting, but at 200 GBytes per platter (aka 100 GBytes per side), it wasn't terribly cost-effective, nor was it particularly power-stingy. But, as I pointed out in a November follow-up, you don't necessarily need to be perfect when you're the only game in town!

Hitachi's accomplishment didn't remain sole-sourced long, of course, given the hyper-competitiveness of the HDD industry. Seagate launched a four-platter (250 GByte/platter) configuration in June of 2007, along with a Samsung paper-launch of a three-platter (333 GByte/platter) configuration in that same timeframe. Western Digital waited until late July 2007 to unveil its own four-platter configuration, and recent data suggests that Samsung's products are finally shipping in volume (as well that 1 TByte drives have dipped below $150!).

The last two weeks show that vendors' competitive juices have by no means abated even in the slightest. On July 9^th, Hitachi finally got its 1 TByte drive down to a 3-platter configuration, the 7200 RPM Deskstar 7K1000.B, with product shipments forecasted to begin this same month. Until your drive sample arrives, content yourself (or not) with the 'Dawn of the Tera Era' animation clip, a follow-up to my earlier-mentioned (and equally questionable entertainment) Get Perpendicular.

One day later (what a strange coincidence, eh?), Samsung released the world's first 1.5 TByte HDD, high-end member of the 7200.11 product family, scheduled to enter production next month. At 375 GBytes/platter, it hits a new bit-packing peak for PMR (perpendicular magnetic recording) technology. That same generation of magnetic recording translates to half-GByte 5400 and 7200 RPM 2.5" HDDs, which won't appear until some time in the fourth quarter.

And what about the SSD (solid-state drive) alternative? Although SSDs lag their HDD counterparts on both absolute capacity and cost/GByte metrics, suppliers continue striving to at least maintain pace (if not narrow the gap) with the rotating storage mainstay. Witness, for example, Samsung's 128 GByte SSD announcement which coincidentally (or not, again) hit the wire the same day as Hitachi's HDD release. Samsung accomplishes this 2.5" form factor feat by means of MLC (multi-level cell, aka two-bit-per-cell) NAND flash memory which, as I've written many times in the past, roughly doubles the amount of storage capacity achievable for a given amount of silicon square footage on a given process lithography with the tradeoffs of reduced reliability and read/write performance. Samsung hopes to begin producing prototype quantities of a next-generation 256 GByte MLC-based SSD by year end.

By the way, for those of you who might have heard of the recent SSD-vs-HDD power consumption testing done by Tom's Hardware (which they recently revisited and revised, with notably different and more SSD-positive results), I encourage you to (as StorageMojo finally figured out...sigh...) not draw any sort of definitive conclusions. The original testing methodology was fundamentally limited; Tom's Hardware cranked up both systems via a constantly-running benchmark loop and measured which battery got drained first, but they didn't determine how much work got done (i.e. how many iterations of the benchmark had been completed when the battery gave out in each case). In other words: so what if the SSD-based system didn't last quite as long, if it cranked through substantially more work during the time that it was alive as compared to the HDD-based alternative? The read-vs-write and random-vs-sequential access profiles of the benchmark may or may match your application workload's characteristics, either. And anyway, as Micron pointed out in the comments section of StorageMojo's initial (unnecessarily) inflammatory writeup, several of the SSDs were FPGA-based prototypes, and more generally SSD technology is still new enough that the vendors have not yet focused substantial attention on optimizing their hardware and software for minimal power draw.

Let's revisit the HDD-vs-SSD performance and power consumption metrics in a year or so when SSD technology has had a chance to mature a bit, shall we? Come to think of it, that's make a great EDN hands-on cover story or feature article...

Followup: Hitachi's psychedelic 'The Dawn Of The Tera Era' is now on YouTube. Errr...enjoy...???

And then, of course, there's its 'Get Perpendicular' predecessor...