STORAGE IN TIERED ENVIRONMENT FOR COLDER DATA SEGMENTS

• US 20130166844A1
• Filed: 02/19/2013
• Published: 06/27/2013
• Est. Priority Date: 01/14/2011
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: BENHASE, Michael T., GUPTA, Lokesh M., MELLGREN, Carol S., SANCHEZ, Alfred E.
• Granted Patent: US 8,762,674 B2
• Time in Patent Office: Days
• US Class Current: 711/118
• CPC Class Codes: G06F 3/0608 Saving storage space on storage systems
• CPC Class Codes: G06F 3/0611 in relation to response time
• CPC Class Codes: G06F 3/0649 Lifecycle management
• CPC Class Codes: G06F 3/0685 Hybrid storage combining heterogeneous device types, e.g. hierarchical storage, hybrid arrays

Abstract

Exemplary embodiments for storing data by a processor device in a computing environment are provided. In one embodiment, by way of example only, from a plurality of available data segments, a data segment having a storage activity lower than a predetermined threshold is identified as a colder data segment. A chunk of storage is located to which the colder data segment is assigned. The colder data segment is compressed. The colder data segment is migrated to the chunk of storage. A status of the chunk of storage is maintained in a compression data segment bitmap.

Claims

1. A method for storing data by a processor device in a computing environment, comprising:

identifying, from a plurality of available data segments, a data segment having an storage activity lower than a predetermined threshold as a colder data segment;

locating a chunk of storage to which the colder data segment is assigned;

compressing the colder data segment; and

migrating the colder data segment to the chunk of storage;

wherein a status of the chunk of storage is maintained in a compression data segment bitmap.

2. The method of claim 1, further including performing at least one of:

updating the compression data segment bitmap with information representative of a logical and physical portion of the colder data segment,

staging the colder data segment into cache, and

updating a volume segment table (VST) pointing to the colder data segment represented as a new virtual compressed data segment.

3. The method of claim 2, wherein the compressing the colder data segment is performed in the cache.

4. The method of claim 2, further including, upon an input/output (I/O) operation directed to the colder data segment, performing at least one of:

allocating a non-compressed data segment, and

accessing a virtual extent data segment map to determine the physical portion of the data segment and chunks within the physical portion of the data segment representing the virtual compressed data segment.

5. The method of claim 4, further including, for each of the chunks within the physical portion of the data segment:

staging data from a selected one of the chunks into the cache,

decompressing the data in the cache, and

destaging the decompressed data into the non-compressed data segment.

6. The method of claim 5, further including, subsequent to migrating decompressed data for each of the chunks, performing at least one of:

updating the VST to point to the non-compressed data segment,

freeing each of the chunks,

freeing the virtual compressed data segment, and

allowing the I/O operation.