Log Access Method Storage Control Apparatus, Archive System, and Method of Operation

• US 20140372383A1
• Filed: 06/18/2013
• Published: 12/18/2014
• Est. Priority Date: 06/18/2013
• Status: Active Grant

• Current Assignee: Barracuda Networks Incorporated
• Original Assignee: Barracuda Networks Incorporated
• Inventors: Sipek, Josef
• Granted Patent: US 9,195,668 B2
• Time in Patent Office: Days
• US Class Current: 707/672
• CPC Class Codes: G06F 16/113 Details of archiving lifecycle management in storage systems G06F3/0649; backup systems G06F11/1446
• CPC Class Codes: G06F 16/1752 based on file chunks
• CPC Class Codes: G06F 3/0658 Controller construction arrangements

Abstract

A file shard store includes high performance encoding and compaction circuits. An apparatus and its method of operation avoids duplicate storage of file fragments. A plurality of tables control write operations into a plurality of log segments. Shard keys are transferred to uniquely identify fragments of files which may have been previously stored and associated with one or more of client subscribers. An apparatus comprises a plurality of location/subscription tables, a shard transfer circuit, a storage control circuit, an append-to-log circuit coupled to a large storage array, and a log segment compactor circuit.

Claims

1. A Log Access Method Storage Control Apparatus comprising:

a storage controller communicatively coupled to an external client; and

a plurality of shard location and client subscription tables.

2. The apparatus of claim 1 further comprising:

a shard transfer circuit communicatively coupled to an external client and to an append log circuit, the transfer circuit controlled by the storage controller.

3. The apparatus of claim 2 further comprising:

an append-to-log circuit coupled to a storage array configured as at least one log file, the append-to-log circuit further coupled to the storage controller and to the shard transfer circuit.

4. The apparatus of claim 3 further comprising:

a log compactor circuit coupled to the append-to-log circuit and to at least one log.

5. The apparatus of claim 4 wherein a log is divided into a plurality of log segments.

6. The apparatus of claim 3 further comprising:

a shard meta data store.

7. A method for operating an Log Access Method Storage Control Apparatus comprising:

receiving a get command from a client with one or more shard key,

obtaining a location for each requested shard from a computer readable table, and

delivering the shard(s) to the requesting client.

8. The method of claim 7 further comprising:

checking that the client is associated with the shard in the table.

9. A method for operating a Log Access Method Storage Control Apparatus comprising:

receiving a shard key from a transmitting client, and

sending the transmitting client at least one first code.

10. The method of claim 9 further comprising:

determining from a computer readable table that a shard uniquely associated with the shard key is already stored and associated with the transmitting client, wherein the first code is a success code.

11. The method of claim 10 further comprising:

determining from a computer readable table that a shard uniquely associated with the shard key is already stored but not yet associated with the transmitting client,

appending to a log file associated with the shard, the additional identification of the transmitting client, and updating the table,

wherein, the first code is a success code.

12. The method of claim 11 further comprising:

receiving an unmark code from the transmitting client,

determining from a table that a shard uniquely associated with the shard key is stored and associated with the transmitting client,

appending to a log file associated with the shard, a recission identification of the transmitting client, and updating the table,

wherein the first code is a success code.

13. The method of claim 12 further comprising:

determining from a table that a shard uniquely associated with the shard key is not stored, wherein the first code is a shard transmission request code,

receiving the shard,

storing to a location,

initializing a log file associated with the shard, its location, and the identification of the transmitting client, and updating the table, and

transmitting second code to the client, a success code.

14. A method for operating a Log Access Method Storage Control Apparatus comprising:

receiving a command and an argument from a transmitting client,

when the command is Exists and the argument is a shard key,

reading a table for presence or absence of the shard key and returning the result to the transmitting client;

when the command is Unmark, and the argument is a shard key,

removing the identity of the transmitting client front a log associated with a shard uniquely associated with the shard key.

when the command is Mark, and the argument is a shard key,

adding the identity of the transmitting client to a log associated with a shard uniquely associated with the shard key.

when the command is Get, and the argument is a shard key,

looking up the location of a shard uniquely associated with the shard key, and

transmitting the shard to the transmitting client, when the command is Put, and the arguments comprise a shard and a shard key,

storing the shard at a location,

storing the shard key, the location, and an identification of the transmitting client into a table, and

initializing a log file with at least the shard key and the identification of the transmitting client.

15. The method of claim 14 further comprising;

writing shard meta data, client subscription, and location data to a file associated with each shard location and client subscription table.

16. A method for reinitializing one of a plurality of shard locator and client subscription tables comprising:

reading a file containing shard meta data, client subscription, and location data associated with a log segment.

17. A method for restoration operation of a file stored in a log access method archive system, the method comprising:

receiving front a requestor a plurality of shard ids and client ids;

looking up a shard location for each shard;

on a condition that the client is a subscriber to each of the shard ids,

retrieving each requested shard; and

transmitting the retrieved shard to the requestor.