公开(公告)号：US20160070618A1

公开(公告)日：2016-03-10

申请号：US14482618

申请日：2014-09-10

Applicant: NetApp, Inc.

Inventor： Anshul Pundir ,  Janice D'Sa ,  Srinath Krishnamachari ,  Ling Zheng

IPC: G06F11/10 ,  G06F11/14 ,  G06F11/20

CPC classification number: G06F11/1438 ,  G06F3/0619 ,  G06F3/064 ,  G06F3/067 ,  G06F3/0679 ,  G06F7/32 ,  G06F11/1088 ,  G06F11/1451 ,  G06F11/1471 ,  G06F11/2069 ,  G06F17/30327 ,  G06F2201/80 ,  G06F2201/805 ,  G06F2201/82 ,  G06F2201/84 ,  G06F2211/104

Abstract: Embodiments herein are directed to efficient crash recovery of persistent metadata managed by a volume layer of a storage input/output (I/O) stack executing on one or more nodes of a cluster. Volume metadata managed by the volume layer is organized as a multi-level dense tree, wherein each level of the dense tree includes volume metadata entries for storing the volume metadata. When a level of the dense tree is full, the volume metadata entries of the level are merged with the next lower level of the dense tree. During a merge operation, two sets of generation IDs may be used in accordance with a double buffer arrangement: a first generation ID for the append buffer that is full (i.e., a merge staging buffer) and a second, incremented generation ID for the append buffer that accepts new volume metadata entries. Upon completion of the merge operation, the lower level (e.g., level 1) to which the merge is directed is assigned the generation ID of the merge staging buffer.

Abstract translation: 这里的实施例涉及由在集群的一个或多个节点上执行的存储输入/输出（I / O）栈的卷层管理的持久元数据的有效崩溃恢复。 由卷层管理的卷元数据组织为多级密集树，其中密集树的每个级别包括用于存储卷元数据的卷元数据条目。 当密集树的级别已满时，级别的卷元数据条目将与密集树的下一个较低级别合并。 在合并操作期间，可以根据双缓冲器布置来使用两组生成ID：用于追加缓冲器的第一代ID（即，合并暂存缓冲器）和用于附加的第二增量生成ID 接受新的卷元数据条目的缓冲区。 在合并操作完成后，向合并处理缓冲器的生成ID分配合并所指示的较低级别（例如，级别1）。