Teradata's Hardware Strategy and Tactics

Teradata's future lies in solid-state memory. That's in line with what Carson Schmidt told me six months ago.

To Teradata's surprise, the solid-state future is imminent. Teradata is 6-9 months further along with solid-state drives (SSD) than it thought a year ago it would be at this point.

Short-term, Teradata is going to increase the number of appliance kinds it sells. I didn't actually get details on anything but the new SSD-based Blurr, but it seems there will be others as well.

Teradata's eventual future is to mix and match parts (especially different kinds of storage) in a more modular product line. Teradata Virtual Storage is of pretty limited value otherwise. I believe Teradata will go modular more emphatically than Teradata itself does, because I think doing so will meet users needs more effectively than if Teradata relies strictly on fixed appliance configurations.

Teradata really likes Intel's Nehalem CPUs, with special reference to multi-threading, QuickPath interconnect, and integrated memory controller. Obviously, Nehalem-based Teradata boxes should be expected in the not too distant future.

Teradata really likes Nehalem's successor Westmere too, and expects to be pretty fast to market with it (faster than with Nehalem) because Nehalem and Westmere are plug-compatible in motherboards.

Teradata will go to 10-gigabit Ethernet for external connectivity on all its equipment, which should improve load performance.

Teradata will also go to 10-gigabit Ethernet to play the Bynet role on appliances. Tests are indicating this improves query performance.

What's more, Teradata believes there will be no practical scale-out limitations with 10-gigabit Ethernet.

Teradata hasn't decided yet what to do about 2.5" SFF (Small Form Factor) disk drives, but is leaning favorably. Benefits would include lower power consumption and smaller cabinets.

Also on Carson's list of "exciting" future technologies is SAS 2.0, which at 6 gigabits/second doubles the I/O bandwidth of SAS 1.0.

Carson is even excited about removing universal power supplies from the cabinets, increasing space for other components.

Teradata picked Intel's Host Bus Adapters for 10-gigabit Ethernet. The switch supplier hasn't been determined yet.

I/O speeds on "random medium blocks" are 520 megabytes/second, vs. 15 MB/second on their fastest conventional disks. And that's limited by SAS 1.0, load-balanced across two devices, not the hardware itself. (2 x 300+ MB/sec turns out to be 520 MB/sec in this case.) No wonder Carson is excited about SAS 2.0.

Teradata is using SAS interfaces for its SSDs, and believes that's unusual, in that other companies are using SATA or Fibre Channel.

Never having had a part fail, Teradata has no real basis to make MTTF (Mean Time To Failure) estimates for its SSDs.

Teradata's SSD appliance design includes no array controllers. The biggest reason is that right now array controllers can't keep up with the SSDs' speed.

In its SSD appliance, Teradata has abandoned RAID, doing mirroring instead via a DBMS feature called Fallback that's been around since Teradata's earliest days. (However, unlike Oracle in Exadata, Teradata continues to use RAID for disks.)

Useful life for Teradata's SSDs is estimated at 5-7 years.

Teradata's SSDs are SLC (Single-Level Cell), as opposed to MLC (Multi-Level Cell).