公开(公告)号：US5506979A

公开(公告)日：1996-04-09

申请号：US679455

申请日：1991-04-02

Applicant: Jaishankar M. Menon

Inventor： Jaishankar M. Menon

IPC: G06F3/06 ,  G06F11/10 ,  G11B20/10 ,  G11B20/18 ,  G06F12/00

CPC classification number: G06F11/1076 ,  G06F11/1008 ,  G11B20/10 ,  G11B20/1833 ,  G06F2003/0697 ,  G06F3/0601

Abstract: Variable length records can be accessed from an array of N+2 synchronous fixed block formatted DASDs in a single pass and in the presence of a single DASD failure if each record is partitioned into a variable number of K fixed length blocks, the blocks are written on the DASDs in column major order K modulo (N+1), the order is constrained such that the first block of each record resides on the (N+l)st DASD, a parity block for each column resides on an (N+2)nd DASD, and each parity block spans N blocks in the same column from the first N DASDs and one block one column offset thereto on the (N+1)st DASD.

Abstract translation: 可以在单次通过的N + 2同步固定块格式的DASD阵列中访问可变长度记录，并且如果每个记录被划分为可变数目的K个固定长度块，则存在单个DASD故障，这些块被写入 在DASD列主要序列K模（N + 1）中，顺序被约束，使得每个记录的第一块驻留在（N + 1）stDASD上，每列的奇偶校验块驻留在（N + 2）nd DASD，并且每个奇偶校验块跨越来自前N个DASD的同一列中的N个块以及在第（N + 1）个DASD上偏移的一个块。

公开(公告)号：US5416915A

公开(公告)日：1995-05-16

申请号：US989245

申请日：1992-12-11

Applicant: Richard L. Mattson ,  Jaishankar M. Menon

Inventor： Richard L. Mattson ,  Jaishankar M. Menon

IPC: G06F3/06 ,  G06F11/10 ,  G06F11/20 ,  G06F11/16 ,  G06F12/06

CPC classification number: G06F11/1076 ,  G06F11/1008 ,  G06F3/0601 ,  G06F2003/0697

Abstract: A method and system for minimizing seek affinity and enhancing write sensitivity in a direct access storage device (DASD) array are disclosed. SEEK affinity and WRITE efficiency are preserved in which logical cylinders, as recorded on the DASD array, are managed as individual log structured files (LSF). Tracks or segments of data and parity blocks having the same or different parity group affinity and stored on the same or different DASD cylindrical addresses are written into a directory managed buffer. Blocks having the same parity affinity and written to counterpart cylinders are written out from the buffer to spare space reserved as part of each DASD cylinder. Otherwise, blocks are updated in place in their DASD array location.

Abstract translation: 公开了一种在直接访问存储设备（DASD）阵列中最小化搜寻亲和度并提高写入灵敏度的方法和系统。 保留SEEK亲和力和写入效率，其中记录在DASD阵列上的逻辑柱面作为单独的日志结构化文件（LSF）进行管理。 具有相同或不同的奇偶校验组相似度并存储在相同或不同DASD圆柱形地址上的数据和奇偶校验块的轨迹或奇偶校验块被写入目录管理缓冲器。 具有相同奇偶性相似性并写入对应气瓶的块从缓冲器中写出作为每个DASD气缸一部分保留的备用空间。 否则，在其DASD数组位置更新块。

公开(公告)号：US5579475A

公开(公告)日：1996-11-26

申请号：US518955

申请日：1995-08-24

Applicant: Miguel M. Blaum ,  James T. Brady ,  Jehoshua Bruck ,  Jaishankar M. Menon

Inventor： Miguel M. Blaum ,  James T. Brady ,  Jehoshua Bruck ,  Jaishankar M. Menon

IPC: G06F11/10 ,  G06F11/20 ,  G11B20/18 ,  G11C29/00 ,  H03M13/11 ,  G06F11/34

CPC classification number: G11C29/88 ,  G06F11/1076 ,  G11B20/1833 ,  H03M13/11 ,  G06F11/1012

Abstract: The data contents of up to two concurrently failed or erased DASDs can be reconstituted where the data is distributed across M DASDs as an (M-1)*M block array and where (1) the (M-1)st DASD contains the simple parity taken over each of the array diagonals in diagonal major order in the same mode (odd/even) as that exhibited by the major diagonal of the array and (2) where the M-th DASD contains the simple even parity over each of the rows in row major order. Relatedly, short write updates require fewer operations for data blocks located off the major data array diagonal.

Abstract translation: 最多两个并发故障或擦除的DASD的数据内容可以重新组合，其中数据作为（M-1）* M块阵列分布在M DASD上，其中（1）（M-1）st DASD包含简单 在与阵列的主对角线所显示的相同模式（奇数/偶数）中的对角线主序列中的每个阵列对角线上获得的奇偶校验，以及（2）其中第M个DASD包含每个阵列对角线上的简单偶数奇偶校验 行行主要顺序。 相关地，对于位于主数据阵列对角线上的数据块，短写入更新需要更少的操作。

公开(公告)号：US5577211A

公开(公告)日：1996-11-19

申请号：US241920

申请日：1994-05-11

Applicant: Narasimhareddy L. Annapareddy ,  James T. Brady ,  Damon W. Finney ,  Richard F. Freitas ,  Michael H. Hartung ,  Michael A. Ko ,  Noah R. Mendelsohn ,  Jaishankar M. Menon ,  David R. Nowlen ,  Shin-Yuan Tzou

Inventor： Narasimhareddy L. Annapareddy ,  James T. Brady ,  Damon W. Finney ,  Richard F. Freitas ,  Michael H. Hartung ,  Michael A. Ko ,  Noah R. Mendelsohn ,  Jaishankar M. Menon ,  David R. Nowlen ,  Shin-Yuan Tzou

IPC: G06F13/00 ,  H04L29/06 ,  G06F13/38 ,  G06F15/16

CPC classification number: H04L29/06

Abstract: A computing system includes plural nodes that are connected by a communications network. Each node comprises a communications interface that enables an exchange of messages with other nodes. A ready queue is maintained in a node and includes plural message entries, each message entry indicating an output message control data structure. The node further includes memory for storing plural output message control data structures, each including one or more chained further monrtol data structures that define data comprising a message or a portion of a message that is to be dispatched. Control data structures that are chained from an output messsage control data structure exhibit a sequence dependincy. A processor is controlled by the ready queue and enables dispatch of portions of the message designated by an output message control data structure and associated further control structures. The processor prevents dispatch of one portion of a message prior to dispatch of another portion of the message upon which the first portion is dependent even if message transmissions are interrupted.

Abstract translation: 计算系统包括通过通信网络连接的多个节点。 每个节点包括能够与其他节点交换消息的通信接口。 在节点中维护就绪队列，并且包括多个消息条目，每个消息条目指示输出消息控制数据结构。 该节点还包括用于存储多个输出消息控制数据结构的存储器，每个包括一个或多个链接的另外的monrtol数据结构，该数据结构定义包括要发送的消息或消息的一部分的数据。 从输出消息控制数据结构链接的控制数据结构表现出序列依赖性。 处理器由就绪队列控制，并且使得能够分派由输出消息控制数据结构和相关联的进一步控制结构指定的消息的部分。 即使消息传输被中断，处理器在发送消息的另一部分之前防止了第一部分依赖于消息的一部分的分派。

公开(公告)号：US5263145A

公开(公告)日：1993-11-16

申请号：US528999

申请日：1990-05-24

Applicant: James T. Brady ,  Ruth E. Cintron ,  Stephen Goldstein ,  Jean H. Wang Ju ,  Jaishankar M. Menon

Inventor： James T. Brady ,  Ruth E. Cintron ,  Stephen Goldstein ,  Jean H. Wang Ju ,  Jaishankar M. Menon

IPC: G06F3/06 ,  G06F11/10 ,  G06F13/42 ,  G11B20/10 ,  G11B20/18 ,  G06F12/02

CPC classification number: G06F11/1076 ,  G06F11/1008 ,  G06F3/0601 ,  G11B20/10 ,  G11B20/1833 ,  G06F2003/0692

Abstract: A method and means for managing access to a logical track of KN blocks of which K are parity blocks. The KN blocks are distributed and stored in an array of N DASDs having K blocks per physical track per DASD. The array includes control means for securing synchronous access to selectable ones of the DASDs responsive to each access request. The method involves (a) formatting the blocks onto the array using a row major order modulus as the metric for balancing the data rate and concurrency (the number of DASDs bound per access) and (b) executing the random sequences of large and small access requests over the array.

公开(公告)号：US5542066A

公开(公告)日：1996-07-30

申请号：US172527

申请日：1993-12-23

Applicant: Richard L. Mattson ,  Jaishankar M. Menon

Inventor： Richard L. Mattson ,  Jaishankar M. Menon

IPC: G06F11/10 ,  G06F11/34 ,  G06F12/08 ,  G11C29/00 ,  G06F12/00

CPC classification number: G06F12/0804 ,  G06F11/1008 ,  G06F11/3409 ,  G06F11/3485 ,  G06F12/0866 ,  G11C29/74

Abstract: A controller for a disk array with parity and sparing includes a non-volatile cache memory and optimizes the destaging process for blocks from the cache memory to both maximize the cache hit ratio and minimize disk utilization. The invention provides a method for organizing the disk array into segments and dividing the cache memory into groups in order of least recently used memory locations and then determining metrics that permit the disk array controller to identify the cache memory locations having the most dirty blocks by segment and group and to identify the utilization rates of the disks. These characteristics are considered to determine when, what, and how to destage. For example, in terms of maximizing the cache hit ratio, when the percentage of dirty blocks in a particular group of the cache memory locations reaches a predetermined level, destaging is begun. The destaging operation continues until the percentage of dirty blocks decreases to a predetermined level. In terms of minimizing disk utilization, all of the dirty blocks in a segment having the most dirty blocks in a group are destaged.

Abstract translation: 用于具有奇偶校验和备用的磁盘阵列的控制器包括非易失性高速缓存存储器，并且优化来自高速缓冲存储器的块的降级处理以最大化高速缓存命中率并最小化磁盘利用率。 本发明提供了一种用于将磁盘阵列组织成段并将高速缓存存储器按照最近最少使用的存储器位置的顺序划分成组的方法，然后确定允许磁盘阵列控制器通过片段识别具有最脏块的高速缓冲存储器位置的度量 并分组并确定磁盘的使用率。 这些特征被认为是决定什么时候，什么以及如何去世的。 例如，就最大化高速缓存命中率而言，当高速缓冲存储器位置的特定组中的脏块的百分比达到预定水平时，开始着陆。 破坏操作继续，直到脏块的百分比减小到预定水平。 在最小化磁盘利用率的情况下，具有组中最脏的块的段中的所有脏块都将被排除。

公开(公告)号：US5459853A

公开(公告)日：1995-10-17

申请号：US979740

申请日：1992-11-23

Applicant: John S. Best ,  Steven R. Hetzler ,  Roger F. Hoyt ,  Jaishankar M. Menon ,  Michael F. Mitoma

Inventor： John S. Best ,  Steven R. Hetzler ,  Roger F. Hoyt ,  Jaishankar M. Menon ,  Michael F. Mitoma

IPC: G06F3/06 ,  G06F11/10 ,  G11B20/10 ,  G11B20/12 ,  G06F12/00 ,  G06F12/04

CPC classification number: G06F11/1076 ,  G06F11/1008 ,  G06F3/0601 ,  G06F2003/0697 ,  G11B20/1258

Abstract: A method for operating a synchronized array of fixed block (FBA) formatted Direct Access Storage Devices (DASDs) to store and update variable-length (CKD) formatted records. This method is suitable for use with DASDs that obtain high recording density by using read and write head technology requiring "micro-jogging" to adjust for differing read and write head alignment or banded disk architecture having a higher block count in the outer tracks than in the inner tracks. Magneto-resistive heads may require micro-jogging to realign the write head for recording after reading the physical track location. The invention employs a DASD staggered array architecture having logical tracks consisting of diagonal-major sequences of consecutive blocks arranged in a predetermined wrap-around manner such as a topological cylinder or torus. The minimum necessary number of DASDs (N) in the staggered array is limited by the fixed block size (B), the interblock gap size (G), the average DASD data transfer rate (D), and the micro-jog delay time (T). A (N+1).sup.th DASD may be added to record the parity of each diagonal-major sequence for improved fault-tolerance.

Abstract translation: 一种用于操作固定块（FBA）格式化的直接存取存储设备（DASD）的同步阵列以存储和更新可变长度（CKD）格式记录的方法。 该方法适用于通过使用需要“微点动”的读写头技术来获得高记录密度的DASD，用于调整不同的读写头对准或带外磁盘结构，在外轨道中具有较高的块数，而不是 内轨。 在读取物理轨道位置之后，磁阻头可能需要微型点动来重新对准写入头进行记录。 本发明采用具有逻辑轨迹的DASD交错阵列架构，其逻辑轨道由以诸如拓扑柱面或环面的预定绕环方式布置的连续块的对角线主序列组成。 交错阵列中DASD（N）的最小必需数量受固定块大小（B），块间间隙大小（G），平均DASD数据传输速率（D）和微点动延迟时间（D） T）。 可以添加A（N + 1）DASD来记录每个对角线主序列的奇偶校验，以提高容错能力。

公开(公告)号：US5301297A

公开(公告)日：1994-04-05

申请号：US725696

申请日：1991-07-03

Applicant: Jaishankar M. Menon ,  Leighton C. Wood, Jr.

Inventor： Jaishankar M. Menon ,  Leighton C. Wood, Jr.

IPC: G06F3/06 ,  G06F11/10 ,  G06F11/20 ,  G06F12/16 ,  G06F12/06

CPC classification number: G06F11/1076 ,  G06F2211/1045

Abstract: A method and apparatus teaching insertion of addressing indirection to form and to access an array hierarchy expressly permitting the concurrency of a high level RAID array, the bandwidth and degraded mode operation sustainable by a lower level RAID array, and after a DASD failure minimum spanning involvement when the array is rebuilding and rewriting missing data to a spare logical device. Also, disclosed are the accessing of variable length records on the array hierarchy; array hierarchy in which RAID 5 arrays have dissimilar number of logic devices (lower level RAID arrays) and interleave depths; formation of logical arrays using fractional storage defined onto real DASD subsets; and the defining of logical devices onto DASDs distributed in the same or different physical clusters of DASDs and the rebuild operation thereof.

Abstract translation: 一种教导插入寻址间接以形成和访问阵列层次结构的方法和装置，明确允许高级RAID阵列的并发，由较低级RAID阵列可持续的带宽和降级模式操作，以及在DASD故障最小跨越涉及之后 当阵列正在重建并将缺失的数据重写到备用逻辑设备时。 另外，公开了访问数组层级上的可变长度记录; 阵列层次结构，其中RAID 5阵列具有不同数量的逻辑器件（较低级RAID阵列）和交错深度; 使用定义在实际DASD子集上的分数存储来形成逻辑阵列; 以及在分布在相同或不同的DASD物理簇中的DASD上的逻辑设备的定义及其重建操作。

公开(公告)号：US5271012A

公开(公告)日：1993-12-14

申请号：US653596

申请日：1991-02-11

Applicant: Miguel M. Blaum ,  Hsieh T. Hao ,  Richard L. Mattson ,  Jaishankar M. Menon

Inventor： Miguel M. Blaum ,  Hsieh T. Hao ,  Richard L. Mattson ,  Jaishankar M. Menon

IPC: G06F3/06 ,  G06F11/10 ,  G06F11/16 ,  G06F11/20 ,  G06F12/16 ,  G11B20/18 ,  G11C29/00 ,  H03M13/11

CPC classification number: G11C29/88 ,  G06F11/1092 ,  G11B20/1833 ,  H03M13/11 ,  G06F11/1012

Abstract: A method and means for encoding data written onto an array of M synchronous DASDs and for rebuilding onto spare DASD array capacity when up to two array DASD fail. Data is mapped into the DASD array using an (M-1)*M data array as the storage model where M is a prime number. Pairs of simple parities are recursively encoded over data in respective diagonal major and intersecting row major order array directions. The encoding traverse covering a topologically cylindrical path. Rebuilding data upon unavailability of no more than two DASDs merely requires accessing the data array and repeating the encoding step where the diagonals are oppositely sloped and writing the rebuilt array back to onto M DASDs inclusive of the spare capacity.

公开(公告)号：US5574882A

公开(公告)日：1996-11-12

申请号：US397817

申请日：1995-03-03

Applicant: Jaishankar M. Menon ,  James C. Wyllie ,  Geoffrey A. Riegel

Inventor： Jaishankar M. Menon ,  James C. Wyllie ,  Geoffrey A. Riegel

IPC: G06F3/06 ,  G06F11/10 ,  G06F12/00 ,  G06F13/00

CPC classification number: G06F11/1076 ,  G06F2211/1009

Abstract: A system and method are provided that is used by software implemented Redundancy Array of Inexpensive Disk (RAID) arrays to achieve adequate performance and reliability, as well as to improve performance or low cost hardware Raids. The enhancements to the basic RAID implementation speeds up recovery time for software RAIDS. A method is provided for storing data in an array of storage devices. A plurality of block locations on the storage devices are logically arranged as a parity group wherein a parity block stored in a block location as part of a parity group is logically derived from the combination of data blocks stored in the parity group, and each block in a parity group is stored on a different storage device. A plurality of parity groups are grouped into a parity group set. A request is received to write a new data block location on a storage device. The old data block stored at the block location is read. The new data block is written to the block location. When the parity set is in an unmodified state prior to the current write, an indicator is written to the storage device that the parity group set is in a modified state. In a preferred embodiment, this enhancement uses a bit map stored on disk, called Parity Group Set, (PGS) bit map, to mark inconsistent parity groups, replacing the Non-Volatile Random Access Memory, (NVRAM) used for similar purposes by hardware RAIDs. Further enhancements optimized sequential input/output, (I/O) data stream.

Abstract translation: 提供了一种由软件实现的廉价磁盘冗余阵列（RAID）阵列使用的系统和方法，以实现足够的性能和可靠性，以及提高性能或低成本硬件RAID。 基本RAID实施的增强可以加快软件RAIDS的恢复时间。 提供了一种用于将数据存储在存储设备阵列中的方法。 存储设备上的多个块位置被逻辑地布置为奇偶校验组，其中作为奇偶校验组的一部分存储在块位置中的奇偶校验块从存储在奇偶校验组中的数据块的组合逻辑地导出，并且每个块 奇偶校验组存储在不同的存储设备上。 多个奇偶校验组被分组成奇偶校验组集合。 接收到在存储设备上写入新的数据块位置的请求。 读取存储在块位置的旧数据块。 新数据块被写入块位置。 当奇偶校验集在当前写入之前处于未修改状态时，将指示符写入存储设备，奇偶校验组集合处于修改状态。 在优选实施例中，该增强使用存储在磁盘上的位图（称为奇偶校验集合（PGS）位图）来标记不一致的奇偶校验组，用硬件替代用于类似目的的非易失性随机存取存储器（NVRAM） RAID 进一步增强优化的顺序输入/输出（I / O）数据流。