Improved Linux InfiniBand support near

Linux developers have nearly finished their work supporting storage protocols and clustering interfaces for InfiniBand

The Linux kernel is on track to include full support the high-speed networking standard InfiniBand by the end of this summer.

Roland Dreier, one of the Linux kernel maintainers handling InfiniBand support and a senior software engineer at hardware vendor Topspin Communications, told ZDNet UK this week that he and his fellow InfiniBand maintainers have almost completed their work enabling support for storage protocols and clustering APIs running over Infiniband in the Linux kernel.

Currently the latest version of the kernel, 2.6.11, only has limited InfiniBand support.

"What's available in the kernel now is the most basic set of drivers that are useful," said Dreier. "It has low-level support for InfiniBand hardware and support for the IP networking protocol over InfiniBand."

One of the main clustering APIs that Dreier and his team are working on is MPI, a protocol for passing messages between parallel processors.

Dreier said that supporting storage protocols and MPI will be a significant advancement for the kernel.

"MPI is the key API for scientific computing," said Dreier. "That combined with storage is the way most people are using InfiniBand right now."

At present, many companies running InfiniBand on Linux are relying on proprietary drivers, but this is likely to change when full InfiniBand support is added.

"I think it will make a big difference to the InfiniBand world when this support becomes available in the official kernel," said Dreier. "Probably in the next couple of quarters we will see people migrating to open source drivers."

Even though the protocols and APIs are nearly complete, it's not certain they will make the next version of the Linux kernel, 2.6.12. "If 2.6.12 comes out within the next month or goes into code freeze, we won't be able to add the features in time," said Dreier. "They will be merged into the kernel tree in the next few months."

Other operating systems including Solaris, HP-UX and Windows have some support for InfiniBand, although Dreier claims that Linux is the major platform being used for the networking technology.

"There are of the order of tens of thousands of new nodes getting involved in InfiniBand every quarter," said Dreier. "At least three quarters of those are Linux nodes."

At present, high-performance computing tends to rely on expensive specialist hardware, but InfiniBand makes it possible on clusters of commodity servers, although this will require chipset makers such as Intel to add InfiniBand support for these servers.