Lemon: An MPI parallel I/O library for data encapsulation using LIME

We introduce Lemon, an MPI parallel I/O library that provides efficient parallel I/O of both binary and metadata on massively parallel architectures. Motivated by the demands of the Lattice Quantum Chromodynamics community, the data is stored in the SciDAC Lattice QCD Interchange Message Encapsulation format. This format allows for storing large blocks of binary data and corresponding metadata in the same file. Even if designed for LQCD needs, this format might be useful for any application with this type of data profile. The design, implementation and application of Lemon are described. We conclude with presenting the excellent scaling properties of Lemon on state-of-the-art high performance computers.Program summaryProgram title: LemonCatalogue identifier: AELP_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AELP_v1_0.htmlProgram obtainable from: CPC Program Library, Queenʼs University, Belfast, N. IrelandLicensing provisions: GNU General Public License version 3No. of lines in distributed program, including test data, etc.: 32 860No. of bytes in distributed program, including test data, etc.: 223 762Distribution format: tar.gzProgramming language: MPI and CComputer: Any which supports MPI I/OOperating system: AnyHas the code been vectorised or parallelised?: Yes. Includes MPI directives.RAM: Depending on input usedClassification: 11.5External routines: MPINature of problem: Distributed file I/O with metadataSolution method: MPI parallel I/O based implementation of LIME formatRunning time: Varies depending on file and architecture size, in the order of seconds