公开(公告)号：US09400816B1

公开(公告)日：2016-07-26

申请号：US14144031

申请日：2013-12-30

Applicant: GOOGLE INC.

Inventor： Andrey Gubarev ,  Eric Veach ,  Alexander Thomson ,  Nathan Bales ,  Laramie Leavitt ,  Dale Woodford ,  Sergey Melnik

IPC: G06F17/30

CPC classification number: G06F17/30321 ,  G06F17/30327 ,  G06F17/30548

Abstract: A multiversioned position-space indexing system is disclosed. The system includes data structures for maintaining a multiversioned position space including a multi-versioned filter merge list which represents many versions of a changing position space in a very compact form and a position shift map which describes how to translate stored positions in many different log-structured merge tree layers into logical positions at a particular timestamp. Each log-structured merge tree layer can be divided into two sublayers: a final sublayer and a correction sublayer. The final sublayer contains index entries added after the layer's start timestamp and remain live as of the layer's final timestamp as well as deletion makers for index entries that were inserted before the layer's start timestamp, but deleted before the layer's final timestamp. The correction layer contains index entries that were both created and deleted between the start and end timestamps of the layer.

Abstract translation: 公开了一种多重位置空间索引系统。 该系统包括用于维护多版本位置空间的数据结构，其包括多版本过滤器合并列表，其以非常紧凑的形式表示改变位置空间的许多版本;以及位置移动图，其描述如何在许多不同的对数位置中翻译存储的位置， 将结构化合并树层划分成特定时间戳的逻辑位置。 每个日志结构合并树层可以分为两个子层：最后的子层和校正子层。 最后一个子层包含在图层的开始时间戳之后添加的索引条目，并保留图层最终时间戳的活动，以及在图层的开始时间戳之前插入的索引条目的删除制作者，但在图层的最后时间戳之前被删除。 校正层包含在层的开始和结束时间戳之间创建和删除的索引条目。