IBM still operates the fastest supercomputer in the industry, but rival HP has more of them in operation, according to a closely watched global survey released Wednesday.

HP has passed IBM in the number of supercomputers in operation and enjoys the largest market share, according to a list of the Top 500 supercomputers that was compiled by university computer researchers in the United States and Germany. But IBM's Blue Gene/L supercomputer, installed at Lawrence Livermore National Laboratory in California, ranked first on the list and IBM claims it is the market share leader when vendors are ranked by combined computing performance.

The biannual list is being released Wednesday to coincide with the International Supercomputing Conference in Dresden, Germany.

HP grew its market share to 40.4% with 202 systems, while IBM's share fell to 38.4% with 192 systems. In the previous report in November 2006, IBM's share was 47.2% with 236 systems, to HP's 31.6% with 158 systems.

IBM said it holds a 42% share of the supercomputer market when it's based on the combined processing power of each vendor's equipment. Its Blue Gene/L took the No.1 spot with a "sustained performance" of 280.6 trillion operations per second, or teraflops. Flops is an acronym for "floating point operations per second," a measure of computing performance.

On Tuesday IBM announced a new supercomputer, Blue Gene/P, which will have three times the processing power of the Blue Gene/L. A two-rack test model of the P made it into the top 30 on the list, achieving 20.86 teraflops (T flops), although IBM said that properly configured, the P may be able to hit 3 petaflops (P flops), or 1,000 trillion calculations per second.

Sun, which held only a 1.4% share with only seven systems deployed, is making a concerted effort to pursue the supercomputer market. Sun announced Tuesday it is building a supercomputer, codenamed "Constellation," which is designed to reach 1 petaflop. It is building Constellation at the Texas Advanced Computing Center (TACC) at the University of Texas at Austin. Sun received $29.6 million of a total $59 million National Science Foundation grant to build Constellation, while the balance of $29.4 million will go toward operational costs, said Faith Singer, a TACC spokeswoman.

The IDG News Service is a Network World affiliate.