System and method for striped mirror re-synchronization by logical partition rather than stripe units
AssigneeInternational Business Machines Corporation
InventorsGerald Francis McBrearty, Johnny Meng-Han Shieh
Life of this patent
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Abstract
Striped mirrors are re-synchronized by logical partition rather than by stripe unit for stale partitions. While re-synchronizing physical partitions, data is serialized across both the stripe unit and the real partition region. The re-sync Read operation uses the normal logical partition offsets to read on a physical partition boundary rather than using the stripe units. In so doing, a single disk in a striped mirror can be replaced without re-synchronizing the entire mirror. The resync Read is not broken up into individual stripe unit reads.
Claims23
A data processing system implemented method for resynchronizing a striped mirror, comprising:
- receiving information that a disk is stale, wherein the disk is associated with a mirror;
- and
- performing a resynchronizing Read for a block on only the stale disk, wherein prior to performing a resynchronizing Read, the method comprises:
- serializing an IO request across both a stripe unit and a partition boundary.
A data processing system implemented method for resynchronizing a striped mirror, comprising:
- serializing IO requests to both a logical region boundary and stripe units
- issuing a re-sync Read IO request for a block;
- determining an available mirror for the block;
- issuing a single Read for reading the block from a boundary on a first disk, wherein the first disk is associated with the available mirror;
- and
- issuing a single Write for writing the block from a boundary on a second disk, wherein the second disk is stale.
A data processing system implemented method for resynchronizing a striped mirror, comprising:
- issuing a Read IO request for a first block;
- determining at least two stripe units associated with the first block;
- identifying a physical region for each stripe unit;
- issuing separate Read IO requests for each stripe unit associated with the block for each physical region;
- issuing a re-sync Read IO request for a second block;
- determining an available mirror for the second block;
- issuing a single Read IO request for reading the second block from a boundary on a second physical region, wherein the second physical region is associated with the available mirror;
- and
- issuing a single Write IO request for writing the second block from a boundary on a third region, wherein the third region is stale.
A data processing system for resynchronizing a striped mirror, comprising:
- receiving means for receiving information that a disk is stale, wherein the disk is associated with a mirror;
- performing means for perform a resynchronizing Read for a block on only the stale disk;
- and
- serializing means for serializing an IO request across both a stripe unit and a partition boundary.
A data processing system for resynchronizing a striped mirror, comprising:
- serializing means for serializing IO requests to both stripe units and a logical region boundary;
- issuing means for issuing a re-sync Read IO request for a block;
- determining means for determining an available mirror for the block;
- issuing means for issuing a single Read for reading the block from a boundary on a first disk, wherein the first disk is associated with the available mirror;
- and
- issuing means for issuing a single Write for writing the block from a boundary on a second disk, wherein the second disk is stale.
A data processing system for resynchronizing a striped mirror, comprising:
- issuing means for issuing a Read request IO request for a first block;
- determining means for determining at least two stripe units associated with the first block;
- identifying means for identifying a physical region for each stripe unit;
- issuing means for issuing separate Reads for each stripe unit associated with the block for each physical region;
- issuing means for issuing a re-sync Read IO request for a second block;
- determining an available mirror for the second block;
- issuing means for issuing a single Read for reading the second block from a boundary on a second physical region, wherein the second physical region is associated with the available mirror;
- and
- issuing means for issuing a single Write for writing the second block from a boundary on a third region, wherein the third region is stale.
A computer program product for implementing a method for resynchronizing a striped mirror, comprising:
- receiving instructions for receiving information that a disk is stale, wherein the disk is associated with a mirror;
- performing instructions for performing a resynchronizing Read for a block on only the stale disk;
- and
- serializing instructions for serializing an IO request across both a stripe unit and a partition boundary.
Dependencies are inferred from the claim text.