Virtual machine rollback

• US 10,055,146 B1
• Filed: 12/30/2014
• Issued: 08/21/2018
• Est. Priority Date: 12/30/2014
• Status: Active Grant

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Inventors: Natanzon, Assaf, Don, Arieh, Derbeko, Philip
• Primary Examiner(s): Parikh, Kalpit
• Application Number:
  US14/585,258
• Time in Patent Office: 1,330 Days
• CPC Class Codes: G06F 12/0868 Data transfer between cache memory and other subsystems, e.g. storage devices or host systems
• CPC Class Codes: G06F 12/0897 with two or more cache hierarchy levels with multilevel cache hierarchies G06F12/0811
• CPC Class Codes: G06F 2009/45579 I/O management, e.g. providing access to device drivers or storage
• CPC Class Codes: G06F 2009/45591 Monitoring or debugging support
• CPC Class Codes: G06F 2212/1024 Latency reduction
• CPC Class Codes: G06F 2212/1032 Reliability improvement, data loss prevention, degraded operation etc
• CPC Class Codes: G06F 2212/154 Networked environment
• CPC Class Codes: G06F 2212/163 Server or database system
• CPC Class Codes: G06F 2212/225 Hybrid cache memory, e.g. having both volatile and non-volatile portions
• CPC Class Codes: G06F 2212/312 In storage controller
• CPC Class Codes: G06F 3/0611 in relation to response time
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/065 Replication mechanisms
• CPC Class Codes: G06F 3/0688 Non-volatile semiconductor memory arrays
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD
• CPC Class Codes: G06F 9/45558 Hypervisor-specific management and integration aspects
• CPC Class Codes: G06F 9/467 Transactional memory G06F9/528 takes precedence

Abstract

A method, system, and computer program product for data consistency, the system comprising receiving an IO from an application at a server cache, writing the IO to a location on the server cache as to not overwrite the previous data to which the IO is directed, updating, in the server cache, the location of the data to correspond to the location where the IO was written and recording the location of the previous data in a log.

Claims

1. A system for data consistency, the system comprising:

a storage system;

an application running on a server;

wherein the application comprises a virtual machine;

the server with a server cache;

wherein the server cache has a log;

wherein the server cache is enabled to store memory information for the application;

computer-executable logic operating in memory, wherein the computer-executable program logic is configured to enable one or more processors to execute;

receiving a current IO from the application at the server cache, the current IO updating data stored on the server cache;

writing the current IO to a location on a portion of the server cache segregated to the application by a hypervisor;

wherein the application runs in the hypervisor;

as to not overwrite previous data to which the current IO is directed;

wherein the hypervisor is enabled to segregate writes from virtual machines to different areas in the server cache;

updating, in the server cache, a location index of the data to correspond to the location where the current IO was written;

recording a location of the previous data in the log;

wherein the computer executable logic is further configured for;

periodically transferring portions of content stored on the server cache to the storage system;

wherein the storage system stores IO written to the a disk image of the application and the server cache represents IO written to memory, wherein the server cache has DRAM and Flash;

wherein the writing the current IO so as to not to overwrite the previous data to which the current IO is directed further comprises;

writing the previous data to the Flash; and

writing the current IO in the DRAM; and

wherein the recording the location of the previous data in the log includes recording the location of the previous data written in the Flash.

2. The system of claim 1 further comprising storage;

wherein the storage is enabled to store data of the application.

3. The system of claim 1 the computer logic further configured to enable:

receiving a request for a previous point in time for the application;

reading the log to find the previous point in time;

using the log, portion of the application stored on storage, and the server cache to create the previous point in time; and

exposing the previous point of time to the application.

4. The system of claim 3, wherein the computer logic is further configured to enable:

rolling the data of the application stored on the storage to the previous point in time.

13. The system of claim 1 wherein the system performs rollback of a VM or an application by rolling a replicated image back in time and by rolling memory back in time using a log.

5. A computer program product comprising:

a non-transitory computer readable medium encoded with computer executable program code for replication of data, the code configured to enable the execution of;

receiving an a current IO from an application at a server cache, the current IO updating data stored on the server cache;

wherein the application comprises a virtual machine;

writing the current IO to a location on a portion of the server cache segregated to the application by a hypervisor;

wherein the application runs in the hypervisor;

as to not overwrite previous data to which the current IO is directed;

wherein the hypervisor is enabled to segregate writes from virtual machines to different areas in the server cache;

updating, in the server cache, a location index of the data to correspond to the location where the current IO was written;

recording the a location of the previous data in a log;

periodically transferring portions of content stored on the server cache to a storage system;

wherein the storage system stores IO written to a disk image of the application and the server cache represents IO written to memory, wherein the server cache has DRAM and Flash, and wherein the writing the current IO so as to not to overwrite the previous data to which the current IO is directed further comprises;

writing the previous data to the Flash; and

writing the current IO in the DRAM;

and wherein the recording the location of the previous data in the log includes recording the location of the previous data written in the Flash.

6. The computer program product of claim 5 wherein storage is enabled to store data of the application.

7. The computer program product of claim 5 wherein the code further configured to enable the execution of:

receiving a request for a previous point in time for the application;

reading the log to find the previous point in time;

using the log and the server cache to create the previous point in time; and

exposing the previous point of time to the application.

8. The computer program product of claim 5 wherein the code further configured to enable the execution of:

rolling the data of the application stored on the storage to the previous point in time.

14. The computer program product of claim 5 wherein the code is further configured to perform rollback of a VM or an application by rolling a replicated image back in time and by rolling memory back in time using a log.

9. A computer implemented method comprising:

receiving a current IO from an application at a server cache, the current IO updating data stored on the server cache;

wherein the application comprises a virtual machine;

writing the current IO to a location on a portion of the server cache segregated to the application by a hypervisor;

wherein the application runs in the hypervisor;

as to not overwrite previous data to which the current IO is directed;

wherein the hypervisor is enabled to segregate writes from virtual machines to different areas in the server cache;

updating, in the server cache, a location index of the data to correspond to the location where the current IO was written;

recording the a location of the previous data in a log;

periodically transferring portions of content stored on the server cache to a storage system;

wherein the storage system stores IO written to the a disk image of the application and the server cache represents IO written to memory, wherein the server cache has DRAM and Flash, and wherein the writing the current IO so as to not to overwrite the previous data to which the current IO is directed further comprises;

writing the previous data to the Flash; and

writing the current IO in the DRAM; and

wherein the recording the location of the previous data in the log includes recording the location of the previous data written in the Flash.

10. The computer implemented method of claim 9 wherein storage is enabled to store data of the application.

11. The computer implemented method of claim 9 further comprising

receiving a request for a previous point in time for the application;

reading the log to find the previous point in time;

using the log and the server cache to create the previous point in time; and

exposing the previous point of time to the application.

12. The computer implemented method of claim 9 further comprising:

rolling the data of the application stored on the storage to the previous point in time.