Sun, Intel Optimize Solaris for 'Nehalem'

The two-year Sun Microsystems and Intel joint development and marketing agreement to offer performance, scalability, power management and virtualization enhancements in Solaris on x86 systems is continuing to show results. Sun officials say while some advancements already have been rolled out, the key goal was to optimize Solaris for Intel's new processor architecture, code-named Nehalem. Intel releases a Nehalem EP or Xeon 5500 series of chips for two-socket systems March 30.

Sun Microsystems and Intel for the past two years have been working to optimize the Solaris operating system on the Xeon chip platform.

Since the February 2007 announcement of the development and marketing deal, Sun and Intel have announced several steps in the partnership, including several new Sun blade and rack servers powered by Xeon chips and the May 2008 launch of Solaris 10 Release 05/8, which continued the optimization of the operating system on the Intel architecture.

However, while there have been advances, at the forefront of the work has been Intel's new "Nehalem" microarchitecture, said Herb Hinstorff, director of business management at Sun.

Intel is launching the quad-core Nehalem EP-now known as the Xeon 5500 series-for two-socket systems March 30, and will roll out another chip series for servers with four or more sockets later in 2009. The new architecture offers enhanced power management, performance and virtualization capabilities, as well as an integrated memory controller similar to what Advanced Micro Devices offers with Opteron.

"This generation of Nehalem is where people are going to really see big benefits" of the Sun-Intel work with Solaris, Hinstorff said.

In the area of performance benefits, Hinstorff said Solaris is optimized to take advantage of new instruction sets in the Nehalem architecture, as well as such features as the QuickPath chip-to-chip interconnect and Turbo Boost speed ramping technologies. In addition, Solaris has been enhanced to work well with the upgraded multithreading capabilities in Nehalem, he said.

"You get full utility out of all those capabilities," he said.

Sun's ZFS file system also is a good match for the performance upgrades in the new chip, Hinstorff said. Sun March 30 will announce new benchmarks that illustrate Solaris' performance advantages with Nehalem.

In power efficiency, the Power Aware Dispatcher in Solaris and OpenSolaris-which helps power down processing cores that aren't being fully utilized-enhances the energy efficiency features in the Xeon 5500 chip, which leads to a 20 percent drop in power usage for idle cores, Hinstorff said.

A blog post on Sun's Web site March 29 by Eric Saxe, a Sun engineer working on Solaris, further outlined the working relationship between the OS and the Nehalem architecture:

"The Solaris Power Aware Dispatcher (PAD) has increased awareness of the Intel Xeon processor 5500 series, such that the workload can be efficiently utilized on available hardware threads, with benefits for shared pipelines, shared caches, and shared sockets. The Solaris PAD is able to communicate what processor resources are being used by the operating system, and which are not.The Solaris kernel now has the ability to utilize those parts of the processor that are active, and continue to avoid doing work on those parts that are powered down.Together, these two capabilities work together resulting in greater power efficiency without losing any performance. This integration enables the Intel Xeon processor 5500 series to enter into a deeper C-state, and do so with less latency. These capabilities are enabled by default."

Hinstorff said the DTrace troubleshooting tool and PowerTop feature-which keeps track of CPU utilization-in Solaris will further enhance the energy efficiency capabilities of Nehalem.

"Mating [DTrace] with PowerTop ... allows PowerTop to provide a much better way of observing exactly where the power is being used in the chip," Hinstorff said.

With its Fault Management Architecture, Solaris can help monitor the health of the cores in Nehalem.

"In this way, systems can keep on running ... and it's transparent to [the] user," Hinstorff said.

Gordon Haff, an analyst with Illuminata, said the work Sun and Intel have done with Solaris on x86 makes sense, particularly given the large number of users-particularly developers-who use the operating system.

"There's a big Solaris base out there," Haff said.

Haff also pointed out that major OEMs are supporting Solaris on their Intel-based systems. Most recently, Hewlett-Packard and Sun inked a deal in February in which HP will distribute and support Solaris 10 on its ProLiant and blade servers.