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Title: Purple L1 Milestone Review Panel GPFS Functionality and Performance

Technical Report ·
DOI:https://doi.org/10.2172/896605· OSTI ID:896605

The GPFS deliverable for the Purple system requires the functionality and performance necessary for ASC I/O needs. The functionality includes POSIX and MPIIO compatibility, and multi-TB file capability across the entire machine. The bandwidth performance required is 122.15 GB/s, as necessary for productive and defensive I/O requirements, and the metadata performance requirement is 5,000 file stats per second. To determine success for this deliverable, several tools are employed. For functionality testing of POSIX, 10TB-files, and high-node-count capability, the parallel file system bandwidth performance test IOR is used. IOR is an MPI-coordinated application that can write and then read to a single shared file or to an individual file per process and check the data integrity of the file(s). The MPIIO functionality is tested with the MPIIO test suite from the MPICH library. Bandwidth performance is tested using IOR for the required 122.15 GB/s sustained write. All IOR tests are performanced with data checking enabled. Metadata performance is tested after ''aging'' the file system with 80% data block usage and 20% inode usage. The fdtree metadata test is expected to create/remove a large directory/file structure in under 20 minutes time, akin to interactive metadata usage. Multiple (10) instances of ''ls -lR'', each performing over 100K stats, are run concurrently in different large directories to demonstrate 5,000 stats/sec.

Research Organization:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Organization:
USDOE
DOE Contract Number:
W-7405-ENG-48
OSTI ID:
896605
Report Number(s):
UCRL-TR-226526; TRN: US200703%%858
Country of Publication:
United States
Language:
English