Resource allocation throttling in remote data mirroring system

• US 20070028139A1
• Filed: 07/17/2006
• Published: 02/01/2007
• Est. Priority Date: 03/30/1998
• Status: Active Grant

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: EMC Corporation (Dell Technologies Inc.)
• Inventors: Losh, Michael, Wahl, Steven
• Granted Patent: US 7,562,250 B2
• Time in Patent Office: Days
• US Class Current: 714/6
• CPC Class Codes: G06F 11/2056 by mirroring
• CPC Class Codes: G06F 11/2066 Optimisation of the communication load
• CPC Class Codes: G06F 11/2069 Management of state, configuration or failover
• CPC Class Codes: G06F 11/2074 Asynchronous techniques
• CPC Class Codes: G06F 9/50 Allocation of resources, e.g. of the central processing unit [CPU]
• CPC Class Codes: G06F 9/5016 the resource being the memory
• CPC Class Codes: H04L 41/0654 using network fault recovery ring fault isolation or reconfiguration in loop networks without recovery actions by a network management system H04L12/437
• CPC Class Codes: H04L 41/0806 for initial configuration or provisioning, e.g. plug-and-play
• CPC Class Codes: H04L 41/0893 Assignment of logical groups to network elements
• CPC Class Codes: H04L 41/22 comprising specially adapted graphical user interfaces [GUI]
• CPC Class Codes: H04L 43/0817 by checking functioning
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06

Abstract

A computer network remote data mirroring system writes update data both to a local data device and to a local, chronologically sequenced journal storage area, or writelog device. A graphical user interface enables a user to create and configure throttles, which are user-defined tests and actions evaluated by the primary mirror daemon to regulate network bandwidth, CPU, and writelog device utilization during data update mirroring. Network bandwidth throttling enables a predetermined portion of the network bandwidth to be assigned to remote data mirroring based on user-selected criteria. CPU throttling enables a user to control the amount of time the local data storage unit will wait prior to returning control to applications after an update. Writelog device throttling prevents a memory overflow condition by dynamically assigning memory to the writelog device by chaining writelog device extensions to the writelog device.

Claims

1-3. -3. (canceled)

4. A method of mirroring data, comprising:

receiving a sequence of data updates;

writing each update to a journal storage in a manner that preserves the place of each data update within the sequence.

5. A method as recited in claim 4, further comprising receiving an indication that the journal storage is or is about to become full with previously-stored updates that are still required to be retained;

and dynamically allocating additional storage locations to the journal storage.

6. A method as recited in claim 4, wherein the primary local data storage comprises a first local storage device and the journal storage comprises a second local storage device.

7. A method as recited in claim 4, further comprising returning control to an application or other process from which a particular data update was received only after that data update has been written to both the primary local data storage and the journal storage.

8. A method as recited in claim 4, wherein writing an update to the journal storage comprises writing the update to a journal cache and subsequently reading the update from the cache and writing the update to a journal storage location on disk.

9. A method as recited in claim 4, further comprising allowing no more than a prescribed number of updates to accumulate in the journal storage.

10. A method as recited in claim 9, wherein allowing no more than a prescribed number of updates to accumulate in the journal storage includes sending one or more updates across a network to a remote mirror location and deleting the one or more updates from the journal storage once confirmation is received that the updates were received and incorporated successfully at the remote mirror location.

11. A method as recited in claim 9, wherein the prescribed number is configurable.

12. A method as recited in claim 4, further comprising retrieving as a group a plurality of updates stored in the journal storage and sending the retrieved updates one-by-one, in the sequence in which they were written into the journal storage, to a remote mirror location.

13. A computer system, comprising:

a local data device configured to store data associated with one or more applications or other processes;

a writelog device configured to store updates to data stored in the local data device; and

a processor configured to;

receive a sequence of updates from the one or more applications or other processes; and

write each update to the writelog device in a manner that preserves the place of each update within the sequence

14. A system as recited in claim 13, wherein the processor is further configured to receive an indication that the writelog device is or is about to become full with previously-stored updates that are still required to be retained;

and dynamically allocate additional storage locations to store updates from the one or more applications or other processes.

15. A system as recited in claim 13, wherein the processor is further configured to return control to an application or other process from which a particular data update was received only after that data update has been written to both the local data device and the writelog device.

16. A system as recited in claim 13, wherein the processor is further configured to allow no more than a prescribed number of updates to accumulate in the writelog device.

17. A system as recited in claim 16, wherein the processor is configured to allow no more than a prescribed number of updates to accumulate in the writelog device at least in part by mirroring one or more updates to a remote mirror location.

18. A computer program product for mirroring data, the computer program product being embodied in a computer readable medium and comprising computer instructions for:

receiving a sequence of data updates;

writing each update to a journal storage in a manner that preserves the place of each data update within the sequence.

19. A computer program product as in claim 18, further comprising computer instructions for receiving an indication that the journal storage is or is about to become full with previously-stored updates that are still required to be retained;

and dynamically allocating additional storage locations to the journal storage.

20. A computer program product as in claim 18, further comprising computer instructions for returning control to an application or other process from which a particular data update was received only after that data update has been written to both the primary local data storage and the journal storage.

21. A computer program product as in claim 18, further comprising computer instructions for allowing no more than a prescribed number of updates to accumulate in the journal storage.

22. A computer program product as in claim 18, wherein writing an update to the journal storage comprises writing the update to a journal cache and subsequently reading the update from the cache and writing the update to a journal storage location on disk.

23. A computer program product as in claim 18, further comprising computer instructions for retrieving as a group a plurality of updates stored in the journal storage and sending the retrieved updates one-by-one, in the sequence in which they were written into the journal storage, to a remote mirror location.