Reducing read operations and branches in file system policy checks

• US 10,067,943 B2
• Filed: 12/22/2017
• Issued: 09/04/2018
• Est. Priority Date: 09/15/2016
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Hasegawa, Tohru, Itagaki, Hiroshi, Matsui, Sosuke, Mitsuma, Shinsuke, Miyamura, Tsuyoshi, Yamamoto, Noriko
• Primary Examiner(s): Shanmugasundaram, Kannan
• Application Number:
  US15/851,937
• Publication Number:
  US 20180101539A1
• Time in Patent Office: 256 Days
• CPC Class Codes: G06F 11/1448 Management of the data involved in backup or backup restore
• CPC Class Codes: G06F 11/1451 by selection of backup contents
• CPC Class Codes: G06F 11/1469 Backup restoration techniques
• CPC Class Codes: G06F 16/122 using management policies backup systems G06F11/1446; file migration policies for HSM systems G06F16/185
• CPC Class Codes: G06F 16/128 Details of file system snapshots on the file-level, e.g. snapshot creation, administration, deletion use of snapshots for error detection or correction G06F11/14, G06F11/16
• CPC Class Codes: G06F 16/16 File or folder operations, e.g. details of user interfaces specifically adapted to file systems
• CPC Class Codes: G06F 21/6218 to a system of files or objects, e.g. local or distributed file system or database

Abstract

A method to identify data elements conforming to a policy includes receiving a request to identify data elements in an input set of data elements that conform to one or more requested policies. According to the method, policy output information describing data elements that conform to a requested policy are saved in association with the requested policy. In response to receiving a subsequent request to identify data elements in a subsequent set of data elements that conform to the requested policy, the method includes outputting the saved policy output information based on the policy output information having been saved in association with the requested policy. A computer program product and a system, configured with processors and a memory that can store saved policy information, can implement the method.

Claims

1. A computer-implemented method for

identifying files conforming to a policy, the method comprising:

receiving, by at least one processor, a first request to determine a first set of files

included in a first snapshot of a file system that conform to at least one input policy;

identifying, by the at least one processor, in response to the first request, a first subset of files, included in the first snapshot of the file system, that conform to a requested policy, wherein the requested policy is included in the at least one input policy;

saving, by the at least one processor, in association with the requested policy, first policy output information descriptive of information nodes (i-nodes) associated with files included in the first subset of files;

including, by the at least one processor, the requested policy in a saved policy set, wherein the at least one processor including the requested policy in the saved policy set is based, at least in part, on the requested policy being not previously included in the saved policy set and a setting configured to include the requested policy in the saved policy set until 2 consecutive requests are received that do not include the requested policy;

identifying a common policy attribute, wherein the common policy attribute is a policy attribute included in each of a first policy and a second policy, wherein the first policy and the second policy are included in the requested policy, and wherein the common policy attribute comprises a rule that a respective data element be associated with a modification date more recent than a threshold date;

combining a check for the common policy attribute included in the first policy with a check for the common policy attribute included in the second policy, wherein the combined check is configured to simultaneously check respective files for the common policy attribute that satisfies both the first policy and the second policy;

receiving, by the at least one processor, a subsequent request to determine files in a subsequent snapshot of the file system that conform to the requested policy;

determining, by the at least one processor, based at least in part on the first policy output information saved in association with the requested policy, a difference set of files comprising files included in the subsequent snapshot of the file system that are not included in the first snapshot of the file system;

identifying, by the at least one processor, a second subset files, included in the difference set of files, that conform to the requested policy by performing at least the combined policy check;

generating second policy output information, wherein the second policy output information is descriptive of files included in the second subset of files; and

outputting, by the at least one processor, the saved first policy output information merged with the second policy output information.