Invalidation of storage control unit cache metadata
First Claim
1. A method for rebuilding metadata in a data storage system having a storage control unit coupled to a host device through a host interface, the metadata formatted into one or more metadata tracks each containing information on customer data stored in one or more corresponding customer data tracks, the method comprising:
- detecting an occurrence of an error in metadata;
identifying a range of customer tracks in which the error is likely to have occurred;
issuing a command through the host interface to invalidate the metadata associated with the identified range of customer tracks;
invalidating the metadata associated with the identified range of customer tracks while the storage control unit remains on-line with the host device; and
rebuilding the invalidated metadata tracks.
3 Assignments
0 Petitions
Accused Products
Abstract
Method, apparatus and program product are provided for the invalidation of faulty metadata in a storage controller coupled to a host device. Faulty metadata may include metadata which no longer matches the associated customer data tracks stored on a DASD or other storage device. When faulty metadata is detected, metadata tracks are selected to be invalidated. A command is received through a host interface, without the controller being taken off-line from the host, and the specified metadata tracks are invalidated. Subsequently, the invalidated metadata tracks are rebuilt. The disclosed method, apparatus and program product invalidate the faulty metadata with reduced impact on normal host/controller I/O operations.
26 Citations
30 Claims
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1. A method for rebuilding metadata in a data storage system having a storage control unit coupled to a host device through a host interface, the metadata formatted into one or more metadata tracks each containing information on customer data stored in one or more corresponding customer data tracks, the method comprising:
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detecting an occurrence of an error in metadata;
identifying a range of customer tracks in which the error is likely to have occurred;
issuing a command through the host interface to invalidate the metadata associated with the identified range of customer tracks;
invalidating the metadata associated with the identified range of customer tracks while the storage control unit remains on-line with the host device; and
rebuilding the invalidated metadata tracks. - View Dependent Claims (2, 3, 4, 5, 6)
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7. A system for rebuilding metadata, comprising:
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a storage controller coupled to a host device through a host interface;
a memory for storing a plurality of metadata tracks, each metadata track associated with at least one customer track stored on a storage device coupled to the storage controller; and
control logic implemented within the storage controller, comprising;
means for detecting an occurrence of an error in metadata;
means for identifying a range of customer tracks in which the error is likely to have occurred;
means for issuing a command through the host interface to invalidate the metadata associated with the identified range of customer tracks;
means for invalidating the metadata associated with the identified tracks while the storage control unit remains on-line with the host device; and
means for rebuilding the invalidated metadata tracks. - View Dependent Claims (8, 9, 10, 11, 12)
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13. A data processing system, comprising:
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a storage controller coupled to a host device through a host interface;
a storage device for storing customer data formatted in customer tracks;
a memory for storing a plurality of metadata tracks, each metadata track associated with at least one customer track; and
a processor programmed to execute instructions for;
detecting an occurrence of an error in metadata;
identifying a range of customer tracks in which the error is likely to have occurred;
receiving a command through the host interface to invalidate the metadata associated with the identified range of customer tracks;
invalidating the metadata associated with the identified range of customer tracks while the storage control unit remains on-line with the host device; and
rebuilding the invalidated metadata tracks. - View Dependent Claims (14, 15, 16, 17, 18)
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19. A storage controller comprising:
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a host interface coupled to a host device;
a storage interface coupled to a storage device on which customer data is stored as a plurality of customer data tracks;
a memory in which metadata is stored, as one or more metadata tracks, each metadata track comprising information on one or more associated customer data tracks;
means for detecting a mismatch between a metadata track and an associated customer data track;
means for receiving a command through the host interface to invalidate one or more selected metadata tracks including the metadata track associated with the customer data track;
means for invalidating the one or more selected metadata tracks while the storage control unit remains on-line with the host device; and
means for rebuilding the one or more invalidated metadata tracks. - View Dependent Claims (20, 21, 22, 23, 24)
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25. A computer program product of a computer readable medium usable with a programmable computer, the computer program product having computer-readable code embodied therein for processing metadata tracks stored in a memory of a data storage controller coupled to a host device through a host interface and to a storage device, the storage device storing customer data formatted as customer data tracks, each metadata track containing information on one or more associated customer data tracks, the computer-readable code comprising instructions for:
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detecting an occurrence of an error in a metadata track;
identifying a range of customer tracks in which the error is likely to have occurred;
receiving a command through the host interface to invalidate the metadata associated with the identified range of customer tracks;
invalidating the metadata associated with the identified range of customer tracks while the storage control unit remains on-line with the host device; and
rebuilding the invalidated metadata tracks. - View Dependent Claims (26, 27, 28, 29, 30)
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Specification