The next version of the core of Linux, the 2.4 kernel, is up and running on Sun Microsystems' top-end E10000 server with 24 processors, Linuxcare chief technology officer Dave Sifry said today. Linuxcare's Anton Blanchard led the effort, he said, and several other programmers helped.
The milestone, however, is not yet proof of Linux's readiness for this high-end environment, which also requires proof of performance, higher-level software, and the faith of corporate buyers. It also needs a production-quality release of the 2.4 kernel, which is arriving months later than expected and is still in beta testing.
Getting an operating system to work on these symmetrical multiprocessing (SMP) computers is a key obstacle as Linux takes on its progenitor, Unix, as well as Microsoft's Windows 2000. Solaris, Sun's version of Unix, works on computers with up to 105 CPUs, Sun has said, and Microsoft has just released a version of Windows that can use 32 CPUs.
Multiprocessor servers are the preferred method for companies to house databases, the core of corporate computing operations that involve thousands of transactions per second. Linux has been largely unable to crack this market, though Intel, Hewlett-Packard, SGI, Dell Computer, NEC, VA Linux Systems and others have begun working to reverse that.
Designing an operating system that can use many processors is difficult because a task running on one chip can't tie up resources such as a communication channel to the network. If the operating system spends too much time waiting for the chips to relinquish resources, the end result is that doubling the number of processors won't come anywhere near to doubling the computer's performance.
In a perfect computer, doubling performance by doubling processors is known as "linear scaling."
Though as yet there are no benchmarks--standard measurements of performance--the Sun system running the 2.4 kernel is fast, Sifry said. For example, it can rebuild the Linux kernel in about 20 seconds, a task that typically takes minutes on a single-processor Intel computer.
"They are seeing near-linear scaling," he said. "The roof's about to get blown out when it comes to Linux 2.4."
Though Linuxcare led the work, another company Sifry declined to name provided the E10000 for the work. Sun, which sees Linux largely as a convenient step on the upgrade path to its own operating system, didn't fund the work.
Linux, unlike most operating systems, is not tightly wedded to a particular CPU. Though it's most commonly used on computers based on 32-bit Intel chips such as the Pentium, Linux also works on Sun's UltraSparc chips, Compaq's Alpha chips, IBM's Power chips, Intel's upcoming Itanium chips, and a host of others.
The 2.4 kernel also has been running on 16-processor Alpha computers, Sifry said.