Generation and use of a time map for accessing a prior image of a storage device
First Claim
Patent Images
1. A data storage system capable of presenting an image of a data store at a past time, the system comprising:
- an I/O processor to intercept I/O requests directed to one or more target units of storage in a data store;
an indexing module to record all write requests intercepted by the I/O processor during a substantially continuous time interval, the indexing module comprising a memory storing, for each write request, a record comprising;
i) identification of target units of storage;
ii) locations of data previously stored in the target units of storage; and
iii) a write time denoting a time at which the write request was received;
a receiver to receive a specification for a past time, the specified past time being selected from the substantially continuous time interval;
a mapping module that uses one or more records to generate a map of the locations of data stored in the target units of storage at the specified past time; and
an image generation module to present an image of the data store at the past time based, at least in part, on the map generated by the mapping module,wherein the map is further stored to facilitate rapid access to the image of the data store at the past time.
8 Assignments
0 Petitions
Accused Products
Abstract
The invention relates to systems, methods, and articles of manufacture for generating an image of a data store at a past time by using a map (e.g., a time map) of the locations of data stored in the data store at the specified past time. The map allows the data storage system to quickly determine the locations of data stored in a data store at a past time, without searching the entire index of records concerning the locations of the past data.
398 Citations
21 Claims
-
1. A data storage system capable of presenting an image of a data store at a past time, the system comprising:
-
an I/O processor to intercept I/O requests directed to one or more target units of storage in a data store; an indexing module to record all write requests intercepted by the I/O processor during a substantially continuous time interval, the indexing module comprising a memory storing, for each write request, a record comprising; i) identification of target units of storage; ii) locations of data previously stored in the target units of storage; and iii) a write time denoting a time at which the write request was received; a receiver to receive a specification for a past time, the specified past time being selected from the substantially continuous time interval; a mapping module that uses one or more records to generate a map of the locations of data stored in the target units of storage at the specified past time; and an image generation module to present an image of the data store at the past time based, at least in part, on the map generated by the mapping module, wherein the map is further stored to facilitate rapid access to the image of the data store at the past time. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A method of generating a time map of a data store for a past time, the method comprising the steps of:
-
creating records of all write requests directed to one or more target units of storage located in a data store during a substantially continuous time interval, each record comprising; i) an identification of at least one target unit of storage; ii) a write time denoting a time at which a write request directed to the at least one target unit of storage was received; and iii) a location to which data stored in the at least one target unit of storage was moved in response to the write request; for a first specified time, generating a time map of the data store at a generation time, by using the records to locate a current location of data for units of storage that were a target of a write request since the first specified time, wherein the first specified time is selected from the substantially continuous time interval; and storing the time map to facilitate rapid access to an image of the data store at the first specified time. - View Dependent Claims (8, 9, 10, 11, 12, 13)
-
-
14. A method of generating an image of a data store at a past time, the method comprising the steps of:
-
intercepting all write requests directed to a plurality of target units of storage in a data store during a substantially continuous time interval; recording, for each write request, an identification of corresponding target units of storage, a location of data previously stored in the corresponding target units of storage, and a write time denoting the write request; mapping an association between the target units of storage and current locations of data previously stored in the target units of storage at a specified past time, the specified past time being selected from the substantially continuous time interval; for the specified past time, generating an image of the data store based, at least in part, on the mapped associations; and storing the time map to facilitate rapid access to the image of the data store at the specified past time. - View Dependent Claims (15, 16, 17, 18, 19, 20, 21)
-
Specification