Abstract: A method for determining path health to conduct a plurality of Input-Output (IO) operations along a healthy path in a network is provided. The present invention may include receiving an IO request from a user and sending the received IO request on a first path. The present invention may include determining a first IO response has exceeded a threshold time on the first path. The present invention may include determining the first path has degraded based on the exceeded threshold time. The present invention may include generating a duplicate IO request and sending on a second path. The present invention may include receiving the duplicated IO response before receiving the original IO response. The present invention may include determining a health state associated with the slower path. The present invention may include refreshing a path state machine based on the determined health state associated with the slow path.

Abstract: The present disclosure relates to a method and an apparatus for failure detection in a storage system. One embodiment provides a method for failure detection in a storage system. The method includes determining an amount of data received by a plurality of switches in the storage system within a predetermined time window so as to obtain a plurality of data amounts; determining a count of check errors detected by the plurality of switches in the data to obtain a plurality of check error counts; and calculating a failure risk for the plurality of switches based on the plurality of data amounts and the plurality of check error counts. Another embodiment of the present invention provides a corresponding apparatus.

Abstract: Method, system and computer program product are disclosed for an error recovery process. One method comprises: program instructions are executable by the processor to perform; determining a component of the computer system related to the error event; determining a quality of service requirement for the component; determining an error recovery process for the error event based on the quality of service requirement; and executing the error recovery process for the error event.

Abstract: A method for determining path health to conduct a plurality of Input-Output (IO) operations along a healthy path in a network is provided. The present invention may include receiving an IO request from a user and sending the received IO request on a first path. The present invention may include determining a first IO response has exceeded a threshold time on the first path. The present invention may include determining the first path has degraded based on the exceeded threshold time. The present invention may include generating a duplicate IO request and sending on a second path. The present invention may include receiving the duplicated IO response before receiving the original IO response. The present invention may include determining a health state associated with the slower path. The present invention may include refreshing a path state machine based on the determined health state associated with the slow path.

Abstract: A computer system can dynamically manage the performance of a data storage system that includes sets of data storage devices. One set of the data storage devices can include read-intensive (RI) solid-state drives (SSDs). The computer system can detect, in response to a specified number of input/output operations per second (IOPS) of data contained on the RI SSDs exceeding the access density of the RI SSDs divided by the portion of data locations of the RI SSDs containing the data, a free area within the RI SSDs having space for additional data. Additional data within the data storage system that has a required access time less than a specified access time threshold and an access frequency less than a specified access frequency threshold can also be detected. In response, the detected additional data can be moved to the free area within the RI SSDs.

Abstract: A method for determining path health to conduct a plurality of Input-Output (IO) operations along a healthy path in a network is provided. The present invention may include receiving an IO request from a user and sending the received IO request on a first path. The present invention may include determining a first IO response has exceeded a threshold time on the first path. The present invention may include determining the first path has degraded based on the exceeded threshold time. The present invention may include generating a duplicate IO request and sending on a second path. The present invention may include receiving the duplicated IO response before receiving the original IO response. The present invention may include determining a health state associated with the slower path. The present invention may include refreshing a path state machine based on the determined health state associated with the slow path.

Abstract: A computer-implemented method, computer program product and system for dynamic granularity of a data storage by identifying tiers of data including units of data with a unit heat index, corresponding to an activity level metric and identifying a tier heat index for each of the tiers of data corresponding to an average of the unit heat index for the units of data within the tiers of data. Furthermore determining a granularity index based on a size of the units of data; calculating a pairing index by comparing the unit heat indexes from the corresponding tiers of data and calculating an efficiency index by comparing the unit heat indexes indicating a percentage of the of units of data within a first tier of data with a higher unit heat index than all of the units of data within a another tier of data with a lower tier heat index.

Abstract: A method and computer system for data storage in a network including receiving, from a user device, a target data to be stored, determining an application associated with the target data in the user device, obtaining a storage pattern generated by monitoring a historical data, the storage pattern indicating storage characteristics of the historical data, the historical data being associated with the application, and controlling a storage of the target data in a network based on the storage pattern.

Abstract: Method, system and computer program product are disclosed for error recovery process. The method comprises: detecting an event of error in a computer system having a plurality of components; obtaining a QoS requirement for the event; determining a strategy for error recovery process based on the obtained QoS requirement; and executing an error recovery process for the event based on the determined strategy for error recovery process.

Abstract: A method to optimize primary and secondary read cache in a data replication environment includes determining contents of a primary read cache at a primary site. The method updates a primary cache map describing the contents and transmits the primary cache map from the primary site to a secondary site. At the secondary site, the method uses the primary cache map to substantially synchronize a secondary read cache with the primary read cache. The method further monitors for updates to the primary read cache and updates the primary cache map accordingly. When a difference between a current primary cache map and a previously transmitted primary cache map reaches a threshold, the method transmits the current primary cache map from the primary site to the secondary site. A corresponding system and computer program product are also disclosed.

Abstract: A computer system can dynamically manage the performance of a data storage system that includes sets of data storage devices. One set of the data storage devices can include read-intensive (RI) solid-state drives (SSDs). The computer system can detect, in response to a specified number of input/output operations per second (IOPS) of data contained on the RI SSDs exceeding the access density of the RI SSDs divided by the portion of data locations of the RI SSDs containing the data, a free area within the RI SSDs having space for additional data. Additional data within the data storage system that has a required access time less than a specified access time threshold and an access frequency less than a specified access frequency threshold can also be detected. In response, the detected additional data can be moved to the free area within the RI SSDs.

Abstract: A computer-implemented method, computer program product and system for dynamic granularity of a data storage by identifying tiers of data including units of data with a unit heat index, corresponding to an activity level metric and identifying a tier heat index for each of the tiers of data corresponding to an average of the unit heat index for the units of data within the tiers of data. Furthermore determining a granularity index based on a size of the units of data; calculating a pairing index by comparing the unit heat indexes from the corresponding tiers of data and calculating an efficiency index by comparing the unit heat indexes indicating a percentage of the of units of data within a first tier of data with a higher unit heat index than all of the units of data within a another tier of data with a lower tier heat index.

Abstract: A method for managing data replicated by an asynchronous copy service. The method includes a computer processor identifying a set of information associated with an element of data stored in an I/O queue. The method further includes modifying an order to transmit elements of data in the I/O queue based, at least in part, on the identified set of information associated with the element of data in the I/O queue. The method further includes transmitting one or more elements of data in the I/O queue, to a secondary storage location that is network accessible, based at least in part on the order to transmit elements of data in the I/O queue.

Abstract: A method and computer system for data storage in a network including receiving, from a user device, a target data to be stored, determining an application associated with the target data in the user device, obtaining a storage pattern generated by monitoring a historical data, the storage pattern indicating storage characteristics of the historical data, the historical data being associated with the application, and controlling a storage of the target data in a network based on the storage pattern.

Abstract: Performance-degrading hardware components in computer storage systems are identified. A timed-out input/output (I/O) operation is detected. Hardware components that include a plurality of types of hardware components involved with the timed-out I/O operation are identified. Involve counts of the hardware components are increased. A plurality of suspicious hardware components are identified based, at least in part, on a hardware hierarchy including one or more types of hardware components. There is at most one suspicious hardware component for each type of hardware component. A performance-degrading hardware component is identified from among the plurality of suspicious hardware components based, at least in part, on the involve counts and the hardware hierarchy. The performance-degrading hardware component is in a layer of the hardware hierarchy that is lower than layers including other suspicious hardware components.

Abstract: A method for optimizing data storage for write-in-free-space workloads is disclosed. In one embodiment, such a method includes receiving a write request to write an updated version of data to a new block address in free space. The new block address maps to a destination extent. The method further determines an old block address, mapping to a source extent, storing a previous version of the data. The method determines whether the source extent is the same as the destination extent. If the source extent is not the same as the destination extent (i.e., the old block address and new block address point to blocks in different extents), the method transfers temperature statistics associated with the old block address from the source extent to the destination extent. The method writes the updated version of the data to the new block address. A corresponding system and computer program product are also disclosed.

Abstract: In a hierarchical storage system, blocks of data selected for auto-tiering migration, are selected based on dynamically adjusted group sizes. Contiguous blocks are organized into default groups. I/O activity of the blocks in a group is monitored. Based on the I/O activity, the default groups may be sub-divided into smaller sub-groups or combined into larger groups, to separate as much as practical, contiguous series of cooler blocks and contiguous series of hotter blocks into respective focused (concentrated) groups or sub-groups. The concentrated group or sub-group may then be migrated according to the average I/O activity of the included blocks. Group configurations are continually and dynamically adjusted according to changing I/O conditions.

Abstract: In a hierarchical storage system, blocks of data selected for auto-tiering migration, are selected based on dynamically adjusted group sizes. Contiguous blocks are organized into default groups. I/O activity of the blocks in a group is monitored. Based on the I/O activity, the default groups may be sub-divided into smaller sub-groups or combined into larger groups, to separate as much as practical, contiguous series of cooler blocks and contiguous series of hotter blocks into respective focused (concentrated) groups or sub-groups. The concentrated group or sub-group may then be migrated according to the average I/O activity of the included blocks. Group configurations are continually and dynamically adjusted according to changing I/O conditions.

Abstract: A method for managing data replicated by an asynchronous copy service. The method includes a computer processor identifying a set of information associated with an element of data stored in an I/O queue. The method further includes modifying an order to transmit elements of data in the I/O queue based, at least in part, on the identified set of information associated with the element of data in the I/O queue. The method further includes transmitting one or more elements of data in the I/O queue, to a secondary storage location that is network accessible, based at least in part on the order to transmit elements of data in the I/O queue.

Abstract: In a hierarchical storage system, blocks of data selected for auto-tiering migration, are selected based on dynamically adjusted group sizes. Contiguous blocks are organized into default groups. I/O activity of the blocks in a group is monitored. Based on the I/O activity, the default groups may be sub-divided into smaller sub-groups or combined into larger groups, to separate as much as practical, contiguous series of cooler blocks and contiguous series of hotter blocks into respective focused (concentrated) groups or sub-groups. The concentrated group or sub-group may then be migrated according to the average I/O activity of the included blocks. Group configurations are continually and dynamically adjusted according to changing I/O conditions.