Before moving to a quad-core processor, take a look at the software licensing schemes for your enterprise applications.
Advanced Micro Devices Inc. (AMD) plans to unleash its native quad-core chip later this year; and Intel is pushing to make quad-core the standard processor for all servers, since the underlying platforms are the same as dual-core, as is the micro-architecture, said Jerry Braun, product manager for Intel Inc.'s Xeon processors.
Heavy workloads from the use of virtualization, Java, expansive databases and enterprise resource planning (ERP) applications, for example, see the most significant performance improvements when going from dual-core to quad-core processors, said Bob Burroughs, Intel's performance marketing manager.
"Workload performance improves 50% to 75% when using quad-core compared to dual core," Burroughs said.
Note that doubling the number of cores on a processor does not double the performance of the chip. On a multicore chip, the cores need to talk to one another, limiting performance, and applications don't always take full advantage of the underlying processing power, an AMD spokesperson explained.
Nevertheless, "from a pricing standpoint, there is no reason not to go to quad-core," said Intel's Braun.
But while the price may be right for the quad-core chip, some software licenses aren't.
Software licensing and multicore processors
Some software vendors evolved their licensing models when multicore chips came into the picture and continue to do so while others kept it simple.
When processors went from single to dual core, Microsoft made the decision to keep its licensing on the processor level, and the company plans to maintain that model in the quad-core era and beyond, said Microsoft representative Maureen Holm.
BEA Systems Inc., an enterprise infrastructure software provider, also licenses per processor, but plan to change the way it charges for licensing over the next couple of months, said BEA representative Kelly Clarke. "We are exploring other alternatives to better support virtualized and multicore environments. We are still working out details and are not at a place just yet to discuss," Clarke said.
Intel spokesman Nick Knuppfer said the majority of software vendors license per socket, so going from a dual-core to a quad-core processor shouldn't affect software licensing in most cases. "From our perspective, charging per socket is the way to do it, and we definitely expressed our opinion about that (to vendors)," Knuppfer said.
AMD's stance on licensing is that users should be able to purchase one software license per processor, regardless of whether the processor is single core, dual core or quad-core, said AMD spokesman Scott Malish. "This customer-centric licensing approach will help facilitate the broad adoption of multicore technology, enabling users to easily and economically migrate to multicore computing," AMD stated.
Other software industry vendors that license per processor include Novell, Red Hat, VMware and Sun. It should be noted that VMware defines a processor as a single physical chip that contains no more than four processor cores, but that it will revisit its licensing policies as x86 processors with more cores become available.
Software licensing gets complicated
For all the software vendors that license per processor, there are exceptions, like Oracle. Oracle has one of the more complicated licensing setups, recognizing each core as a separate processor. The company amended the definition of processor when counting multicore chips and how many licenses are required.
Oracle has four categories for licensing, and each category has a unique processor factor that is used to determine the total number of processor licenses. For instance, the processor factor for the UltraSPARC T1 is 0.25. To determine how many licenses are required, Oracle multiplies that number by the number of cores. A Sun Fire T2000 server with one 1.2 GHz UltraSPARC T1 processor and eight cores requires two licenses (eight multiplied by a processor factor of .25 totals two processor licenses).
Processor factors for AMD and Intel chips are 0.50, so a Hewlett-Packard Co. (HP) ProLiant DL145 G2 with two AMD Opteron 200 series dual-core processors will require two multiplied by two multiplied by a 0.5 processor factor, totaling two processor licenses with a list license fee of $80,000. All other multicore chips, like Sun's UltraSPARC IV, have a 0.75 processor factor, and single core chips have a processor factor of 1.0.
In February, the software company did simplify its licensing for Oracle Standard Edition and Standard Edition One products, so customers can run systems with as many as four processors with no limit on the number of cores.
Under this model, a customer with a server that has four quad-core processors no longer has to buy licenses for each of the 16 cores to run the top-end Enterprise Edition, as was previously required. They can now buy licenses for the four sockets and run Standard Edition, cutting list licensing prices from between $320,000 and $480,000 -- depending on Oracle adjustments that factor in multicore processor performance -- to $60,000, said Nicole Maloney, Zeno Group for Oracle.
IBM value units
IBM's approach is among the most complex. In the third quarter of 2006, IBM software group announced a replacement for its processor-based pricing and introduced the concept of value unit (VU) pricing. Prior to this announcement, customers added up the number of processing cores on which they planned to deploy their database management software (DB2) and multiplied by the price.
But with the introduction of multicore processors, the industry has begun questioning what a processor actually is. IBM believes a processor should be defined as a core, so a processor with two cores (dual-core chip) requires two licenses.
The company developed its VU methodology to standardize the value derived from various processor architectures, normalize the benefits and translate that into how much to charge for software. With multicores, each core is considered a processor, but not all processors require the same number of processor VUs.
To determine the number of processor VU entitlements required for a specific implementation of a product, IBM refers to its pocessor value unit table.
"IBM charges license fees based on performance because there isn't always a correlation between the number of cores on a chip and performance. It makes the most sense to do it this way," said IBM spokesman Jeff Tieszen.
The processor VU of a given product cannot be exchanged, interchanged or aggregated with processor VU entitlements of another product. For example, before the VU metric, a dual-core AMD processor required one license for DB2 software because its performance benefits were about 30% -- not double the performance of a single-core processor.
The IBM VU table shows that a server with one dual-core AMD processor requires 100 VUs -- or 50 VUs per core. If you have a server that has two dual-core AMD processors, then you are required to buy 200 VUs of your DB2 software: two processors x (50 VUs x two cores) equals 200 VUs.
The faster performing dual-core Power5 processor yields more performance than an AMD-based dual-core processor, so it has a higher VU. If you have a server that has two dual-core Power5 processors, then you require 400 VUs of DB2 (100 VUs x four cores equals 400 VUs) -- twice as many VUs as the AMD dual-core example in the previous paragraph.
Licensing could get more complicated as processor technology advances, but that probably won't happen for a while. At least, in technology time anyway.
"I think we are going to see a slow down in the adding of cores as the software industry catches up and becomes more available," said Braun said. "We've gone from single to dual to quad-core in about a year's time. Now we'll see improvements in architectures and power consumption."
Let us know what you think about the story; email: Bridget Botelho, News Writer
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