公开(公告)号：US09390116B1

公开(公告)日：2016-07-12

申请号：US14038673

申请日：2013-09-26

Applicant: EMC Corporation

Inventor： Cheng Li ,  Philip N. Shilane ,  Hyong Shim ,  Stephen Smaldone ,  Grant Wallace ,  Frederick Douglis

IPC: G06F17/30

CPC classification number: G06F17/30336

Abstract: A computer-implemented method for indexing content stored in a cache memory device is disclosed. The method starts with maintaining a fingerprint index having a plurality of fingerprint entries, each mapping a fingerprint to a storage location of a cache memory device, where the cache memory device caches some of data blocks stored in a persistent storage device of a storage system, and where the fingerprint index is a partial index indexing a portion of data stored in the cache memory device. In response to receiving a request to insert a new fingerprint, the method continues with evicting one of the fingerprint entries according to a predetermined eviction algorithm and inserting the new fingerprint into the evicted fingerprint entry.

Abstract translation: 公开了一种用于索引存储在高速缓冲存储器件中的内容的计算机实现的方法。 该方法开始于维护具有多个指纹条目的指纹索引，每个指纹条目将指纹映射到高速缓冲存储器设备的存储位置，其中高速缓存存储器设备缓存存储在存储系统的持久存储设备中的一些数据块， 并且其中指纹索引是索引存储在高速缓冲存储器设备中的数据的一部分的部分索引。 响应于接收到插入新指纹的请求，该方法继续根据预定的逐出算法驱逐指纹条目中的一个，并将新指纹插入被驱逐的指纹条目。

公开(公告)号：US08935446B1

公开(公告)日：2015-01-13

申请号：US14038668

申请日：2013-09-26

Applicant: EMC Corporation

Inventor： Philip N. Shilane ,  Hyong Shim ,  Stephen Smaldone ,  Grant Wallace ,  Frederick Douglis ,  Cheng Li

IPC: G06F13/12 ,  G06F12/08 ,  G06F12/12

CPC classification number: G06F12/0871

Abstract: A computer-implemented method for indexing content stored in a cache memory device is disclosed. The method starts with in response to receiving a first request for caching a first file extent associated with a first file in a cache memory device, generating a first fingerprint based on content of the first file extent. Then the method continues with searching in a fingerprint index based on the first fingerprint to determine whether the first file extent has been stored in the cache memory. In response to determining that a fingerprint entry matching the first fingerprint is found, the method then continues with associating a first identifier identifying the first file extent and the first file with a storage location of the cache memory device obtained from the matching fingerprint entry, without storing the first file extent in the cache memory device.

Abstract translation: 公开了一种用于索引存储在高速缓冲存储器件中的内容的计算机实现的方法。 响应于接收到缓存与高速缓存存储器设备中的第一文件相关联的第一文件盘区的第一请求，基于第一文件盘区的内容生成第一指纹，开始该方法。 然后，该方法继续基于第一指纹在指纹索引中进行搜索，以确定第一文件范围是否已被存储在高速缓冲存储器中。 响应于确定找到与第一指纹匹配的指纹条目，然后该方法继续将识别第一文件盘区的第一标识符和第一文件与从匹配指纹条目获得的高速缓冲存储器装置的存储位置相关联，而没有 将第一文件盘区存储在高速缓冲存储器装置中。

公开(公告)号：US09921963B1

公开(公告)日：2018-03-20

申请号：US14609928

申请日：2015-01-30

Applicant: EMC Corporation

Inventor： Cheng Li ,  Philip Shilane ,  Grant Wallace

IPC: G06F12/08 ,  G06F12/12 ,  G06F12/0831 ,  G06F12/122 ,  G06F12/123

CPC classification number: G06F12/0833 ,  G06F12/12 ,  G06F12/122 ,  G06F12/123 ,  G06F12/127 ,  G06F2212/62 ,  G06F2212/7207

Abstract: A data processing system and methods for performing cache eviction are disclosed. An exemplary method includes maintaining a metadata set for each cache unit of a cache device, wherein the cache device comprises a plurality of cache units, each cache unit having a plurality of segments, calculating a score for each metadata set, and arranging the metadata sets in a list in ascending order from lowest score to highest score. The exemplary method further includes in response to determining that a cache eviction is to be performed, selecting a cache unit corresponding to the metadata set in the list having the lowest score, without recalculating a score for any of the metadata set, and evicting the selected cache unit. The metadata nay include, for example, segment count metadata, validity metadata, last access time (LAT) metadata, and hotness metadata.