Cache-based system management architecture with virtual appliances, network repositories, and virtual appliance transceivers

• US 7,373,451 B2
• Filed: 12/08/2004
• Issued: 05/13/2008
• Est. Priority Date: 12/08/2003
• Status: Active Grant

• Current Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford University)
• Original Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford University)
• Inventors: Brumley, David James, Lam, Monica Sin-Ling, Sapuntzakis, Constantine Paul, Chandra, Ramesh U. V., Zeldovich, Nickolai Borisovich, Rosenblum, Mendel, Chow, James Eugene
• Primary Examiner(s): Sparks, Donald
• Assistant Examiner(s): Farrokh, Hashem
• Application Number:
  US11/007,911
• Publication Number:
  US 20050125513A1
• Time in Patent Office: 1,252 Days
• Field of Search: 711/6
• US Class Current: 711/6
• CPC Class Codes: G06F 11/1456 Hardware arrangements for backup
• CPC Class Codes: G06F 11/1464 for networked environments
• CPC Class Codes: G06F 9/44505 Configuring for program initiating, e.g. using registry, configuration files
• CPC Class Codes: H04L 67/34 involving the movement of software or configuration parameters network booting or remote initial program loading [RIPL] G06F9/4416
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]

Abstract

A cache-based system management architecture named “the Collective” automates system management and supports mobile computing. The Collective manages systems by manipulating virtual appliances, each encapsulating a system state. A virtual appliance (VA) may comprise a virtual network of VAs. Distributed repositories separately storing the VAs and user data. Publishers create and maintain VAs. A user plugs a bootable portable storage device implementing a VA transceiver (VAT) into a host computer. The VAT, comprising a Manager, a Cache Client, and a virtual machine monitor (VMM), authenticates the user, retrieves a copy of the latest version of a subscribed VA from the appropriate network repository, obtains user data, and automatically backs up the user data over the network in the background while running the subscribed VA. Multiple VAs can be run at the same time. With the novel caching protocol and cache charging process, the Collective performs well and has numerous advantages.

Claims

1. A cache-based system management architecture, comprising:

a least one virtual appliance repository storing one or more virtual appliances;

at least one host computer;

a network connecting said virtual appliance repository and said host computer; and

a storage means having a cache optimized for holding virtual disks; and

a fixed function virtual appliance transceiver (VAT) capable of;

performing user authentication;

requesting and receiving said virtual appliances;

binding said virtual appliances to said host computer;

obtaining user data relevant to said virtual appliances;

running said virtual appliances on said host computer;

transmitting altered virtual appliances back to said virtual appliance repository; and

backing up altered or newly created user data over said network.

2. The cache-based system management architecture of claim 1, further comprising:

at least one user data repository connected to said network.

3. The cache-based system management architecture of claim 1, wherein changes made to a user disk are separately stored on one or more version virtual disks in said user data repository.

4. The cache-based system management architecture of claim 3, wherein said version virtual disks are discarded at the end of a user log in session such that said user disk is not affected by said changes.

5. The cache-based system management architecture of claim 3, wherein said changes are committed back to said user data repository, thereby becoming the latest version of said user disk.

6. The cache-based system management architecture of claim 3, wherein said version virtual disks are deleted or ignored, thereby rolling back said user disk to a prior state.

7. The cache-based system management architecture of claim 1, wherein each virtual appliance encapsulates a computer state in a virtual program disk, separating said computer state from user data.

8. The cache-based system management architecture of claim 7, wherein said computer state is composed of a system state, memory, hardware state, or a combination thereof.

9. The cache-based system management architecture of claim 1, wherein said VAT is a self-maintaining virtual appliance.

10. The cache-based system management architecture of claim 1, wherein at least one of said virtual appliances consists of a network of virtual appliances.

11. The cache-based system management architecture of claim 1, wherein said VAT comprises a manager, which includes an operating system with a plurality of device drivers, and a user interface enabling a user to log in and subscribe to said virtual appliances.

12. The cache-based system management architecture of claim 11, wherein said VAT further comprises a virtual machine monitor.

13. The cache-based system management architecture of claim 1, wherein changes made to a virtual program disk of a user-subscribed virtual appliance are separately stored on one or more version virtual disks.

14. The cache-based system management architecture of claim 13, wherein said changes are discarded at the end of a user log in session such that said user-subscribed virtual appliance is not affected by said changes.

15. The cache-based system management architecture of claim 13, wherein said changes are committed back to said virtual appliance repository, thereby becoming the latest version of said user-subscribed virtual appliance.

16. The cache-based system management architecture of claim 13, wherein said version virtual disks are deleted or ignored, thereby rolling back said user-subscribed virtual appliance to a prior state.

17. The cache-based system management architecture of claim 1, further comprising:

a caching subsystem for a) fetching and caching new data and evicting old data;

wherein said new data include metadata for all virtual program disks of said virtual appliances; and

b) upon a first use of a virtual appliance or a new release thereof, automatically charging said storage means with a set of predetermined repository blocks.

18. The cache-based system management architecture of claim 17, wherein said cache subsystem having 1) a log mode in which said cache subsystem continuously backs up user data in order as generated to a user data repository;

2) a checkpoint mode in which said cache subsystem takes snapshots of said user data at a plurality of checkpoints and writes said snapshots to said user data repository; and

     3) a combination mode in which said cache subsystem automatically switches between said log mode and said checkpoint mode.

19. The cache-based system management architecture of claim 1, further comprising:

a caching subsystem having;

a pin list specifying blocks to be pinned in said cache;

a cache writer queue and a cache writer process for centralizing mutations to said cache;

a shim library for issuing reads to files in said cache directly, or on miss, directly to a network repository, after which said shim library generates and places an insert request in said cache writer queue;

a cache charging process for loading said cache with said specified blocks and their priorities and for asking said cache writer process to pin certain blocks in said cache; and

a backup queue and a backup writer process for automatically backing up user data over said network to a user data repository.

20. The cache-based system management architecture of claim 19, wherein said shim library intercepts metadata queries and services said metadata queries with applicable files from a metadata cache.

21. The cache-based system management architecture of claim 19, in which said shim library logs all file accesses to a compressed file.

22. The cache-based system management architecture of claim 19, wherein said cache charging process is adaptive to different levels of network connectivity and supports disconnected operations.

23. The cache-based system management architecture of claim 1, in which said storage means is a portable storage device.

24. The cache-based system management architecture of claim 1, wherein each virtual appliance has a virtual program disk and a starting memory image;

and said virtual program disk is shared by users of said cache-based system management architecture.

25. The cache-based system management architecture of claim 24, wherein said virtual program disk is comprised of a version 0 disk and a series of version virtual disks each capturing differences from a previous version.

26. The cache-based system management architecture of claim 1, wherein each of said virtual appliances is prepared, published, and maintained by a publisher.

27. The cache-based system management architecture of claim 1, wherein each of said virtual appliances has one or more derivatives, each of which is customizable by an end user.

28. A storage device for implementing a cache-based system management architecture, said storage device comprising:

a fixed function virtual appliance transceiver (VAT) capable of;

performing user authentication;

requesting and receiving user-subscribed virtual appliances from one or more virtual appliance repositories;

binding said user-subscribed virtual appliances to a host computer;

obtaining user data relevant to said user-subscribed virtual appliances;

running said user-subscribed virtual appliances on said host computer;

transmitting altered virtual appliances back to respective virtual appliance repositories; and

backing up newly created user data to a user data repository.

29. The storage device of claim 28, wherein said storage device is characterized as portable or mobile.

30. The storage device of claim 28, further comprising:

a cache optimized for holding virtual disks.

31. The storage device of claim 30, wherein said VAT comprises:

a cache writer queue and a cache writer process for centralizing mutations to said cache;

a shim library for issuing reads to files in said cache directly, or on miss, directly to a network repository, after which said shim library generates and places an insert request in said cache writer queue;

a cache charging process for loading said cache with predetermined blocks and their priorities and for asking said cache writer process to pin certain blocks in said cache; and

a backup queue and a backup writer process for automatically backing up user data.

32. The storage device of claim 31, in which said shim library logs all file accesses to a compressed file.

33. The storage device of claim 28, wherein said VAT has 1) a log mode in which user data is continuously backed up;

2) a checkpoint mode in which snapshots of said user data are taken at a plurality of checkpoints and written to a user data repository; and

     3) a combination mode in which said VAT automatically switches between said log mode and said checkpoint mode.

34. The storage device of claim 28, comprising:

an operating system with a plurality of device drivers; and

a user interface enabling a user to log in and subscribe to said virtual appliances.

35. The storage device of claim 34, wherein said user interface comprises one or more Web browsers.

36. The storage device of claim 35, wherein said one or more Web browsers are virtual appliances.

37. The storage device of claim 36, wherein said one or more Web browser virtual appliances are automatically retrieved and activated by said VAT.

38. A computer-readable medium storing a computer program implementing the VAT of claim 28.