Content-type: text/html Manpage of PLFS

PLFS

Section: Environments, Tables, and Troff Macros (7)
Updated: 12/3/2010
Index Return to Main Contents

NAME

PLFS (Parallel Log Structured File System) - General Information

SYNOPSIS

PLFS is a parallel virtual file system that improves concurrent write performance to a shared file.

DESCRIPTION

In many parallel file systems such as Lustre, GPFS, and PanFS, concurrent writes from large numbers of processes to a shared file suffers poor performance due to low-level serialization in the parallel file system. PLFS transparently rearranges concurrrent writes to avoid this serialization.

USING PLFS

There are three ways to use PLFS.

PLFS-MNT (see also plfs(1))

: This interface provides the most transparency to the user. PLFS is mounted as a file system and users simply perform normal file system operations. This option requires FUSE. Although this option gives improved performance, very large-scale parallel applications are encouraged to use the PLFS-MPI-IO interface which provides even larger improvements.

PLFS-MPI-IO

: This is the highest performing interface for PLFS for very large-scale parallel applications. To use this option, applications must use the MPI-IO interface and prepend plfs: to their paths. For example, the path for restart could be plfs:/scratch/user/restart_file This option requires use of an MPI that has been patched with PLFS.

PLFS-API (see also plfs(3))

: Finally, users can interface with PLFS directly by rewriting their applications to use the PLFS API. Although this requires the most user effort, it is possible to use this interface by minimally using just plfs_open(), plfs_write(), plfs_read, and plfs_close(). All PLFS functions are either approximations of POSIX file IO calls or utility functions.

FILES

In order to use any of these interfaces, a configuration file must be present on the system. (see plfsrc(5)).

AUTHORS

PLFS is developed at Los Alamos National Laboratory and is available under LANL LA-CC-08-104. It is hosted at http://sourceforge.net/projects/plfs and more information is available at http://institute.lanl.gov/plfs

plfs(1), plfs(7), plfs_check_config(1), plfs_flatten_index(1), plfs_map(1) plfs(3), plfs(7), is_plfs_file(3), plfs_access(3), plfs_buildtime(3), plfs_chmod(3), plfs_chown(3), plfs_close(3), plfs_create(3), plfs_debug(3), plfs_dump_config(3), plfs_dump_index(3), plfs_flatten_index(3), plfs_get_attr(3), plfs_index_stream(3), plfs_link(3), plfs_merge_indexes(3), plfs_mkdir(3), plfs_mode(3), plfs_open(3), plfs_query(3), plfs_read(3), plfs_readdir(3), plfs_readlink(3), plfs_rename(3), plfs_rmdir(3), plfs_serious_error(3), plfs_set_mpi(3), plfs_stats(3), plfs_statvfs(3), plfs_symlink(3), plfs_sync(3), plfs_trunc(3), plfs_unlink(3), plfs_utime(3), plfs_version(3), plfs_write(3), plfs_wtime(3) plfs(1), plfs(7), plfs_check_config(1), plfsrc(5)

This document was created by man2html, using the manual pages.
Time: 14:34:00 GMT, June 15, 2012