Abstract: In one embodiment, a method includes recording event history information for one or more events associated with an entity; evaluating the event history information for each of the one or more events associated with the entity against a symptom rule, wherein the symptom rule defines a validity state of a diagnosis; issuing a subscription to one or more subscribers, wherein the subscription enables the one or more subscribers to receive diagnosis information; and indicating the validity state of the diagnosis to the subscriber, wherein the recording and the evaluating are performed independently such that the issuing and the event history information and the are substantially decoupled. Other methods are also described, according to various embodiments.

Abstract: In one embodiment, a system includes a storage subsystem having an array of storage devices; a receiving component for receiving an error message; a determining component for determining that the error message indicates that a storage device has failed; a collecting component for collecting an array record having storage device characteristics of the failed storage device; a collating component for collating a candidate record having a plurality of candidate entries; a comparing component for comparing storage device characteristics of the failed storage device of the array record with the storage device characteristics of each of the candidate entries; and an identifying component for identifying a first candidate storage device having storage device characteristics that match the storage device characteristics of the failed storage device or a second candidate storage device having storage device characteristics most similar to the storage device characteristics of the failed storage device.

Abstract: In one embodiment, a method includes reserving extents in a storage pool, reading data from a first portion of an in-use RAID arranged according to a first array configuration, using the reserved extents in the storage pool to store a first portion of the data for writing to the in-use RAID, using one or more free extents in the storage pool or in the in-use RAID to store a second portion of the data for writing to the in-use RAID, writing the data to a second portion of the in-use RAID arranged according to a second array configuration, performing one or more first I/O operations according to the first array configuration, wherein the one or more first I/O operations are performed on the data before the data is read by the data migrating component, and performing one or more second I/O operations according to the second array configuration.

Abstract: In one embodiment, a system includes a recording module adapted for recording event history information for one or more events associated with an entity, an evaluating module adapted for evaluating the event history information for each of the one or more events associated with the entity against a symptom rule, wherein the symptom rule defines a validity state of a diagnosis, an issuing module adapted for issuing a subscription to one or more subscribers, wherein the subscription enables the one or more subscribers to receive diagnosis information, and an indicating module adapted for indicating the validity state of the diagnosis to the subscriber, wherein the recording module and the evaluating module are independent such that the issuing module and the event history information are substantially decoupled. Other systems, methods, and computer program products are also described, according to various embodiments.

Abstract: Mechanisms for ensuring data consistency in a data store are provided. The mechanisms access a parity scrub factor f and perform a check on a data group of the data store. The check on the data group includes performing a parity check on a portion of the data group, the portion being equal to 1/f of the data group, and performing a data verify on the remainder of the data group. The performing of the check is repeated for the entire data store. An offset factor is used to select the portion of the data group for the parity check. In this case, the offset factor may be incremented when the performance of the check on the data group of the data store has been repeated for the entire data store.

Abstract: An apparatus operable with a host and a data storage component for detecting a storage device susceptible to failure under I/O workload is provided. The apparatus includes a selector component for selecting a pair of storage devices in the data storage component. A data migration control component is provided for initiating migration of data from a first to a second storage device of the pair of storage devices. An I/O workload mirroring component is provided for mirroring an I/O workload from a first of the pair of storage devices to a second of the pair of storage devices. A storage device failure detecting component for detecting failure of one of the pair of storage devices is also included. The selector component further comprises a timer component for periodically initiating the selecting.

Abstract: Method, system and computer program product are provided to improve the reliability of data transfers from RAID systems. Although some read errors may be detected by the RAID controller, other errors may not be; undetected errors may affect the integrity of the data. In accordance with the present invention, the host or client issues a first command to the RAID controller to read specified data. After the RAID controller obtains the data from the RAID drives and transmits it to the host, the host verifies the data to detect any errors. If an error is detected by the host, the host issues a second command to the RAID controller to reconstruct the specified data, rather than merely re-read the data. The reconstructed data is then transmitted to the host. Consequently, previously undetected and uncorrected errors may be detected and corrected by the host.

Abstract: An apparatus operable with a host and a data storage component for detecting a storage device susceptible to failure under I/O workload is provided. The apparatus includes a selector component for selecting a pair of storage devices in the data storage component. A data migration control component is provided for initiating migration of data from a first to a second storage device of the pair of storage devices. An I/O workload mirroring component is provided for mirroring an I/O workload from a first of the pair of storage devices to a second of the pair of storage devices. A storage device failure detecting component for detecting failure of one of the pair of storage devices is also included. The selector component further comprises a timer component for periodically initiating the selecting.