Maintaining logical to physical address mapping during in place sector rebuild
An apparatus comprises at least one processing device comprising a processor coupled to a memory that is configured to initiate a read data request utilizing a logical address of a content addressable storage system that maps to a physical address comprising an offset on a storage device that internally maps the offset to a first sector. The processing device is also configured to determine a health of the first sector responsive to the read data request failing, to recover data stored in the first sector responsive to the first sector being a bad sector, and to overwrite the recovered data to the logical address while maintaining the mapping to the physical address by directing a write of the recovered data to the offset to update the internal mapping of the offset in the storage device to a new physical location corresponding to a second sector different than the first sector.
1. An apparatus comprising:
at least one processing device comprising a processor coupled to a memory;
the processing device being configured:
to initiate a read data request utilizing a given logical address of a content addressable storage system, the given logical address mapping to a given physical address comprising a designated physical address offset on a given storage device of the content addressable storage system, the given storage device internally mapping the designated physical address offset to a first sector of the given storage device;
to determine a health of the first sector of the given storage device responsive to the read data request failing;
to recover data stored in the first sector of the given storage device responsive to the determined health indicating that the first sector of the given storage device is a bad sector; and
to overwrite the recovered data to the given logical address while maintaining the mapping of the given logical address to the given physical address in the content addressable storage system by directing a write of the recovered data to the designated physical address offset to update the internal mapping of the designated physical address offset in the given storage device to a new physical location corresponding to a second sector of the given storage device different than the first sector of the given storage device,
wherein the content addressable storage system implements data striping across a plurality of storage devices including the given storage device, and
wherein the at least one processing device is further configured, responsive to the determined health of the first sector of the given storage device indicating that the first sector of the given storage device is a bad sector, initiating a check of one or more additional sectors on one or more additional storage devices in a same stripe as the first sector of the given storage device.
2. The apparatus of claim 1 wherein the mapping of the given logical address to the given physical address comprises a first level of mapping that associates logical addresses of data pages with content-based signatures of the data pages and a second level of mapping that associates the content-based signatures of the data pages with physical storage locations in a plurality of storage devices of the content addressable storage system.
3. The apparatus of claim 2 wherein overwriting the recovered data to the given logical address maintains the first and second levels of mapping.
4. The apparatus of claim 1 wherein the content addressable storage system comprises a Redundant Array of Independent Disks (RAID) storage system.
5. The apparatus of claim 4 wherein a number of data disks in the RAID storage system comprises a prime number k, and wherein a column of the RAID storage system comprises k−1 blocks.
6. The apparatus of claim 4 wherein the RAID storage system implements RAID 6 with the number of data disks being k and the number of parity disks being n, where n is greater than one.
7. The apparatus of claim 1 wherein the given storage device comprises a solid state drive (SSD).
8. The apparatus of claim 1 wherein determining the health of the first sector of the given storage device comprises determining whether the given storage device has failed or whether the given storage device is healthy but the first sector of the given storage device has gone bad.
9. The apparatus of claim 8 wherein the processing device is further configured, responsive to determining that the given storage device has failed, to initiate a rebuild of the given storage device by relocating data stored on the given storage device to at least one additional storage device.
10. The apparatus of claim 1 wherein the at least one processing device is further configured, responsive to the determined health of the first sector of the given storage device indicating that the first sector of the given storage device is a bad sector, initiating a check of one or more additional sectors on the given storage device.
11. The apparatus of claim 1 wherein the read data request comprises a user data read request from at least one application running on a host device configured to utilize the content addressable storage system.
12. The apparatus of claim 1 wherein the read data request comprises a scrubbing mechanism data read for checking a health of the given storage device.
13. A method comprising:
initiating a read data request utilizing a given logical address of a content addressable storage system, the given logical address mapping to a given physical address comprising a designated physical address offset on a given storage device of the content addressable storage system, the given storage device internally mapping the designated physical address offset to a first sector of the given storage device;
determining a health of the first sector of the given storage device responsive to the read data request failing;
recovering data stored in the first sector of the given storage device responsive to the determined health indicating that the first sector of the given storage device is a bad sector; and
overwriting the recovered data to the given logical address while maintaining the mapping of the given logical address to the given physical address in the content addressable storage system by directing a write of the recovered data to the designated physical address offset to update the internal mapping of the designated physical address offset in the given storage device to a new physical location corresponding to a second sector of the given storage device different than the first sector of the given storage device;
wherein the method is implemented by at least one processing device comprising a processor coupled to a memory,
wherein the content addressable storage system implements data striping across a plurality of storage devices including the given storage device, and
further comprising, responsive to the determined health of the first sector of the given storage device indicating that the first sector of the given storage device is a bad sector, initiating a check of one or more additional sectors on one or more additional storage devices in a same stripe as the first sector of the given storage device.
14. The method of claim 13 wherein the mapping of the given logical address to the given physical address comprises a first level of mapping that associates logical addresses of data pages with content-based signatures of the data pages and a second level of mapping that associates the content-based signatures of the data pages with physical storage locations in a plurality of storage devices of the content addressable storage system.
15. The method of claim 14 wherein overwriting the recovered data to the given logical address maintains the first and second levels of mapping.
16. A computer program product comprising a non-transitory processor-readable storage medium having stored therein program code of one or more software programs, wherein the program code when executed by at least one processing device causes said at least one processing device:
to initiate a read data request utilizing a given logical address of a content addressable storage system, the given logical address mapping to a given physical address comprising a designated physical address offset on a given storage device of the content addressable storage system, the given storage device internally mapping the designated physical address offset to a first sector of the given storage device;
to determine a health of the first sector of the given storage device responsive to the read data request failing;
to recover data stored in the first sector of the given storage device responsive to the determined health indicating that the first sector of the given storage device is a bad sector; and
to overwrite the recovered data to the given logical address while maintaining the mapping of the given logical address to the given physical address in the content addressable storage system by directing a write of the recovered data to the designated physical address offset to update the internal mapping of the designated physical address offset in the given storage device to a new physical location corresponding to a second sector of the given storage device different than the first sector of the given storage device,
wherein the content addressable storage system implements data striping across a plurality of storage devices including the given storage device, and
wherein the program code when executed by said at least one processing device further causes said at least one processing device, responsive to the determined health of the first sector of the given storage device indicating that the first sector of the given storage device is a bad sector, to initiate a check of one or more additional sectors on one or more additional storage devices in a same stripe as the first sector of the given storage device.
17. The computer program product of claim 16 wherein the mapping of the given logical address to the given physical address comprises a first level of mapping that associates logical addresses of data pages with content-based signatures of the data pages and a second level of mapping that associates the content-based signatures of the data pages with physical storage locations in a plurality of storage devices of the content addressable storage system.
18. The computer program product of claim 17 wherein overwriting the recovered data to the given logical address maintains the first and second levels of mapping.