Sunday, September 21, 2008

Is Oracle about to embrace MPP?

Oracle's Larry Ellison has some major announcements to make during Oracle's OpenWorld conference this coming week in San Francisco. A few months ago he was promising to announce a "major database innovation", but declined to give further details, so the Oracle community has been speculating furiously.

With a keynote entitled "Extreme Performance," and product announcements coming in areas of grid computing and database acceleration, all the indications are that Oracle is getting serious about problems that require massive scalability, massive throughput, and low latency.

This is an area where Oracle has been falling behind. In Oracle's approach, which independent database analyst Curt Monash calls a "shared everything" architecture, multiple servers belong to the same Oracle Real Application Cluster (RAC) and share a common pool of memory and disk storage. But this approach does not allow Oracle to be run on hundreds or thousands of servers, which is how companies such as Google are solving problems which require large amounts of storage and processing. That sort of massively parallel processing (MPP) requires a "shared nothing" architecture, and internet companies have been rolling their own architectures out of simpler components.

The result is that Oracle "is way behind in the 'scale-out' world," said Paul Vallee, CEO of The Pythian Group, an Ottawa, Ontario-based database services provider. "MySQL is eating its lunch in terms of Internet-scaled deployments."

Oracle's own experts seem to agree. In the abstract for a talk "Oracle's New Database Accelerator: A Technical Overview", Ron Weiss writes:
"New and revolutionary solutions and methodologies are coming together to handle the exploding data volumes real-world systems are being required to store and serve up. Supporting ever-larger databases, with ever-increasing demands for getting "answers" faster, requires a new way to approach the problem."
Weiss's solution uses improvements to storage management, but I doubt that it would satisfy Google's requirements, or even the price/performance requirements of a medium-sized internet media company.

Meanwhile, those who have adopted shared-nothing architectures are feeling the pain too. Having stitched together hundreds or thousands of databases, the problem is how to populate and coordinate them. For example, internet companies' transaction rates are so high that it is not possible to load the day's data during an eight hour nightly load window, and besides, business owners want to see data in near real time. Organizations are adapting a 'trickle ETL' process to populate the data warehouse continuously and with low latency.

So data architects seem to be caught between a rock and a hard place. Either stick with Oracle's shared-everything (or indeed IBM DB2 or Microsoft SQL Server - they have the same approach) and live with the scalability limitations, or move to the wild frontier of shared-nothing, and be prepared to spend a lot of effort managing, populating and coordinating your farm of databases.

Ironically, the answer, as Larry Ellison and his cohorts taught us thirty years ago, is in the relational model. By extending the relational model beyond stored data to include streaming data, SQL can be used to efficiently manage data flowing into and between multiple databases, as well as storage and retrieval within those databases. This creates a scalable shared-nothing system, with databases decoupled from each other, but because the data flow is managed by declarative SQL, it is as manageable as a shared-everything system such as Oracle.

SQLstream is an implementation of this new SQL, and can be applied to continuous ETL, real-time BI and monitoring problems. For example, if there are many data sources for your ETL process, and many servers to be populated, SQLstream can act as a cross-hatch, load-balancing the data, aggregating, and routing each row to the correct database engine with low latency. And because SQLstream's SQL encompasses both data at rest and data in flight, it can correlate data in the warehouse with arriving data.

SQLstream is partnering with companies that are building next-generation data warehousing architectures on Oracle and on other databases. Aeturnum is an exciting new delivery partner for SQLstream with extensive expertise in data warehousing (Netezza) and business intelligence (Pentaho).

Come and see SQLstream at Oracle OpenWorld. We will be at the Aeturnum stand (2716 Moscone South) all this week.


dbscience said...

DB2 has had a shared nothing product for a long time. I've seen it scale well on a 256 MPP CPU computer. I've never understood why IBM didn't promote this functionality better because it is obvious very few people know about it.

Julian Hyde said...

dbscience, I admit I'd never heard of DB2's shared-nothing product. Thanks for enlightening me about it.