Almost lost in the clamor over Sun's expanded partnership with Microsoft on Wednesday was a small acquisition that will bolster Sun's HPC storage offerings. Sun agreed to acquire a majority of the assets of Cluster File Systems.

Among other things, Sun will get the Lustre File System, an open-source software distribution widely used in large computing systems. The company did not disclose the terms of the deal, which it expects to close around the start of Sun's fiscal second quarter, beginning Oct. 1. The acquisition will be immaterial to Sun's earnings per share, the company said in a news release. Cluster is based in Boulder, Colorado.

Lustre can manage and retrieve files on clusters with tens of thousands of nodes. Sun will make Lustre work on Sun's Solaris OS and will continue developing and distributing it for Linux and Solaris on multiple vendors' systems. The file system complements the Sun Constellation Architecture for HPC systems, Sun said.

The two companies aren't strangers. They have already worked together on several large clusters, including one at the Texas Advanced Computing Center with 1.7PB of storage, according to the release. In July, Cluster said Lustre would start using Sun's OpenSolaris ZFS disk file system on Lustre servers that run Linux.