Lustre (file system)Lustre is a type of parallel , generally used for large-scale cluster computing. The name Lustre is a portmanteau word derived from Linux and cluster. Lustre file system software is available under the GNU General Public License (version 2 only) and provides high performance file systems for computer clusters ranging in size from small workgroup clusters to large-scale, multi-site systems. Since June 2005, Lustre has consistently been used by at least half of the top ten, and more than 60 of the top 100 fastest supercomputers in the world, including the world's No.
Unix filesystemIn Unix and operating systems inspired by it, the is considered a central component of the operating system. It was also one of the first parts of the system to be designed and implemented by Ken Thompson in the first experimental version of Unix, dated 1969. As in other operating systems, the filesystem provides information storage and retrieval, and one of several forms of interprocess communication, in that the many small programs that traditionally form a Unix system can store information in files so that other programs can read them, although pipes complemented it in this role starting with the Third Edition.
Year 2038 problemThe year 2038 problem (also known as Y2038, Y2K38, Y2K38 superbug or the Epochalypse) is a time formatting bug in computer systems with representing times after 03:14:07 UTC on 19 January 2038. The problem exists in systems which measure Unix time – the number of seconds elapsed since the Unix epoch (00:00:00 UTC on 1 January 1970) – and store it in a signed 32-bit integer. The data type is only capable of representing integers between −(2^31) and 231 − 1, meaning the latest time that can be properly encoded is 2^31 − 1 seconds after epoch (03:14:07 UTC on 19 January 2038).
XFSXFS is a high-performance 64-bit created by Silicon Graphics, Inc (SGI) in 1993. It was the default file system in SGI's IRIX operating system starting with its version 5.3. XFS was ported to the Linux kernel in 2001; as of June 2014, XFS is supported by most Linux distributions; Red Hat Enterprise Linux uses it as its default file system. XFS excels in the execution of parallel input/output (I/O) operations due to its design, which is based on allocation groups (a type of subdivision of the physical volumes in which XFS is used- also shortened to AGs).
Linux kernelThe Linux kernel is a free and open-source, monolithic, modular, multitasking, Unix-like operating system kernel. It was originally written in 1991 by Linus Torvalds for his i386-based PC, and it was soon adopted as the kernel for the GNU operating system, which was written to be a free (libre) replacement for Unix. Linux is provided under the GNU General Public License version 2 only, but it contains files under other compatible licenses.
Access-control listIn computer security, an access-control list (ACL) is a list of permissions associated with a system resource (object or facility). An ACL specifies which users or system processes are granted access to resources, as well as what operations are allowed on given resourcess. Each entry in a typical ACL specifies a subject and an operation. For instance, If a file object has an ACL that contains , this would give Alice permission to read and write the file and give Bob permission only to read it.
InodeThe inode (index node) is a data structure in a that describes a object such as a or a directory. Each inode stores the attributes and disk block locations of the object's data. File-system object attributes may include metadata (times of last change, access, modification), as well as owner and data. A directory is a list of inodes with their assigned names. The list includes an entry for itself, its parent, and each of its children. There has been uncertainty on the Linux kernel mailing list about the reason for the "i" in "inode".
Hard linkIn computing, a hard link is a directory entry (in a directory-based ) that associates a name with a . Thus, each file must have at least one hard link. Creating additional hard links for a file makes the contents of that file accessible via additional paths (i.e., via different names or in different directories). This causes an alias effect: a process can open the file by any one of its paths and change its content. By contrast, a soft link or to a file is not a direct link to the data itself, but rather a reference to a hard link or another soft link.
