Aggregation of write traffic to a data store

• US 9,361,183 B2
• Filed: 04/22/2014
• Issued: 06/07/2016
• Est. Priority Date: 09/19/2008
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Inventors: Cong, Shi, Brender, Scott, Mehra, Karan, Moss, Darren G., Tipton, William R., Verma, Surendra
• Primary Examiner(s): Wong, Leslie
• Application Number:
  US14/259,065
• Publication Number:
  US 20140237173A1
• Time in Patent Office: 777 Days
• US Class Current: 1/1
• CPC Class Codes: G06F 11/1435 using file system or storage system metadata
• CPC Class Codes: G06F 11/1471 involving logging of persistent data for recovery
• CPC Class Codes: G06F 12/0638 Combination of memories, e.g. ROM and RAM such as to permit replacement or supplementing of words in one module by words in another module address formation of the next microinstruction G06F9/26; masking faults in memories by using spares or by reconfiguring G11C29/70
• CPC Class Codes: G06F 12/121 using replacement algorithms
• CPC Class Codes: G06F 2212/2022 Flash memory
• CPC Class Codes: G06F 2212/205 Hybrid memory, e.g. using both volatile and non-volatile memory
• CPC Class Codes: G06F 2212/221 Static RAM
• CPC Class Codes: G06F 2212/2228 Battery-backed RAM
• CPC Class Codes: G06F 3/0611 in relation to response time
• CPC Class Codes: G06F 3/0656 Data buffering arrangements
• CPC Class Codes: G06F 3/0673 Single storage device
• CPC Class Codes: G11C 7/1006 Data managing, e.g. manipulating data before writing or reading out, data bus switches or control circuits therefor

Abstract

A method and a processing device are provided for sequentially aggregating data to a write log included in a volume of a random-access medium. When data of a received write request is determined to be suitable for sequentially aggregating to a write log, the data may be written to the write log and a remapping tree, for mapping originally intended destinations on the random-access medium to one or more corresponding entries in the write log, may be maintained and updated. At time periods, a checkpoint may be written to the write log. The checkpoint may include information describing entries of the write log. One or more of the checkpoints may be used to recover the write log, at least partially, after a dirty shutdown. Entries of the write log may be drained to respective originally intended destinations upon an occurrence of one of a number of conditions.

Claims

1. A method performed on a computer, the method comprising:

receiving a request to write data to an intended destination on a random access medium;

redirecting the data to an entry in a write log, where the redirected data is written to the write log as opposed to the intended destination on the random access medium per the received request;

mapping, in response to the redirected data being written successfully, the intended destination to the entry of the redirected data in the write log; and

draining, subsequent to the redirecting and in response to the computer not operating on battery power, the entry in the write log to the intended destination on the random access medium.

2. The method of claim 1 where the data is redirected in response to the data not being part of a stream.

3. The method of claim 1 where the data is redirected in response to a size of the data being less than a particular size.

4. The method of claim 1 where the data is redirected via write operations to the write log, and where at least some of the write operations are completed out of order.

5. The method of claim 1 where the draining is further in response to a level of fullness of the write log.

6. The method of claim 1 where the draining is further in response to new entries in the write log not being permitted.

7. A system comprising:

a computer that includes at least one processor and memory that comprises particular instructions that, based on execution, configure the computer to;

receive a request to write data to an intended destination on a random access medium;

redirect the data to an entry in a write log, where the redirected data is written to the write log as opposed to the intended destination on the random access medium per the received request;

map, in response to the redirected data being written successfully, the intended destination to the entry of the redirected data in the write log; and

drain, subsequent to the redirecting and in response to the computer not operating on battery power, the entry in the write log to the intended destination on the random access medium.

8. The system of claim 7 where the data is redirected in response to determining that the data is not part of a stream.

9. The system of claim 7 where the data is redirected in response to determining that a size of the data is less than a particular size.

10. The system of claim 7 where the data is redirected via write operations to the write log, and where at least some of the write operations are completed out of order.

11. The system of claim 7 where the entry is further drained in response to a level of fullness of the write log.

12. The system of claim 7 where the entry is further drained in response to new entries in the write log not being permitted.

13. At least one machine-readable medium comprising:

memory that comprises particular instructions that, based on execution by a computer, configure the computer to perform actions comprising;

receiving a request to write data to an intended destination on a random access medium;

redirecting the data to an entry in a write log, where the redirected data is written to the write log as opposed to the intended destination on the random access medium per the received request; and

mapping, in response to the redirected data being written successfully, the intended destination to the entry of the redirected data in the write log; and

draining, subsequent to the redirecting and in response to the computer not operating on battery power, the entry in the write log to the intended destination on the random access medium.

14. The at least one machine-readable medium of claim 13 where the data is redirected in response to the data not being part of a stream.

15. The at least one machine-readable medium of claim 13 where the data is redirected in response to a size of the data being less than a particular size.

16. The at least one machine-readable medium of claim 13 where the data is redirected via write operations to the write log, and where at least some of the write operations are completed out of order.

17. The at least one machine-readable medium of claim 13, where the draining is further in response to a level of fullness of the write log.

18. The at least one machine-readable medium of claim 13 where the draining is further in response to new entries in the write log not being permitted.