Abstract: An approach to providing failure protection in a loosely-coupled cluster environment. A node in the cluster generates checkpoints of application data in a consistent state for an application that is running on a first node in the cluster. The node sends the checkpoint to one or more of the other nodes in the cluster. The node may also generate log entries of changes in the application data that occur between checkpoints of the application data. The node may send the log entries to other nodes in the cluster. The node may similarly receive external checkpoints and external log entries from other nodes in the cluster. In response to a node failure, the node may start an application on the failed node and recover the application using the external checkpoints and external log entries for the application.

Abstract: Provided are a computer program product, system and method for managing Input/Output (I/O) requests to a storage device. A first entry is located in a volume control table for the logical address to write indicating a version number and a first physical location. The write data is written to a second physical location in the storage device. A second entry is added to the volume control table for the logical address in response to preserve mode being enabled. In response to determining that the preserve mode is enabled, the volume control table is updated to have one of the first and second entry for the logical address point to the second physical location and indicate a current version and to have the first or second entry not indicating the current version to indicate the first physical location and a previous version.

Abstract: For runtime dynamic performance skew elimination in a computer environment, an exemplary computer environment is configured for calculating a rank heats by utilizing a plurality of fine-grained statistics collected at an extent granularity, including considering bandwidth (BW) and input/outputs per second (IOPS) metrics. An adaptive data placement plan is generated to relocate the data. The data is placed among data storage ranks. The data storage ranks are balanced according to the adaptive data placement plan.

Abstract: Input/output (I/O) activity in the multiple tier storage system is monitored to collect statistical information. The statistical information is recurrently transformed into an exponential moving average (EMA) of the I/O activity having a predefined smoothing factor. Data portions in the multiple tier storage system are sorted into buckets of varying temperatures corresponding to the EMA. At least one data migration plan is recurrently generated for matching the sorted data portions to at least one of an available plurality of storage device classes. One data portion sorted into a higher temperature bucket is matched with a higher performance storage device class of the available plurality of storage device classes than another data portion sorted into a lower temperature bucket.

Abstract: Input/output (I/O) activity in the multiple tier storage system is monitored to collect statistical information. The statistical information is recurrently transformed into an exponential moving average (EMA) of the I/O activity having a predefined smoothing factor. Data portions in the multiple tier storage system are sorted into buckets of varying temperatures corresponding to the EMA. At least one data migration plan is recurrently generated for matching the sorted data portions to at least one of an available plurality of storage device classes. One data portion sorted into a higher temperature bucket is matched with a higher performance storage device class of the available plurality of storage device classes than another data portion sorted into a lower temperature bucket.

Abstract: For runtime dynamic performance skew elimination in a computer environment, an exemplary computer environment is configured for calculating a rank heats by utilizing a plurality of fine-grained statistics collected at an extent granularity, including considering bandwidth (BW) and input/outputs per second (IOPS) metrics. An adaptive data placement plan is generated to relocate the data. The data is placed among data storage ranks. The data storage ranks are balanced according to the adaptive data placement plan.

Abstract: For optimizing data placement in a multi-tiered storage system, system configuration data and system performance data is collected. A plurality of data movement plans are generated, based in part on the system configuration data and the system performance data. A conflict between the plurality of data movement plans are arbitrated to form an execution plan. The data movement plans are performed according to the execution plan.

Abstract: A system includes a data collector, a plurality of data placement optimizers, a data placement arbitrator, and a data mover. The data collector is configured to collect system configuration data and system performance data. The plurality of data placement optimizers are each configured to analyze the system configuration data and the system performance data for developing a corresponding data movement plan. The data placement arbitrator is configured to arbitrate conflicts between at least two data movement plans of generated by the plurality of data placement optimizers to form an execution plan. The data mover is configured to perform the data movement plans according to the execution plan.

Abstract: For runtime dynamic performance skew elimination in a computer environment, an exemplary computer environment is configured for calculating a rank heats by utilizing a plurality of fine-grained statistics collected at an extent granularity, including considering bandwidth (BW) and input/outputs per second (IOPS) metrics. An adaptive data placement plan is generated to relocate the data. The data is placed among data storage ranks The data storage ranks are balanced according to the adaptive data placement plan.

Abstract: For runtime dynamic performance skew elimination in a computer environment, an exemplary computer environment is configured for calculating a rank heats by utilizing a plurality of fine-grained statistics collected at an extent granularity, including considering bandwidth (BW) and input/outputs per second (IOPS) metrics. An adaptive data placement plan is generated to relocate the data. The data is placed among data storage ranks The data storage ranks are balanced according to the adaptive data placement plan.

Abstract: A method for replicating I/O performance in data replication environments, such as PPRC environments, is described. In selected embodiments, such a method includes monitoring I/O workload at a primary storage device over a period of time, such as a period of hours, days, or months. The method then generates learning data at the primary storage device describing the I/O workload over the selected time period. The learning data is replicated from the primary storage device to a secondary storage device. The method uses the learning data to optimize the secondary storage device to handle the I/O workload of the primary storage device. This will enable the secondary storage device to provide substantially the same I/O performance as the primary storage device in the event a failover occurs.

Abstract: A method for replicating I/O performance in data replication environments, such as PPRC environments, is described. In selected embodiments, such a method includes monitoring I/O workload at a primary storage device over a period of time, such as a period of hours, days, or months. The method then generates learning data at the primary storage device describing the I/O workload over the selected time period. The learning data is replicated from the primary storage device to a secondary storage device. The method uses the learning data to optimize the secondary storage device to handle the I/O workload of the primary storage device. This will enable the secondary storage device to provide substantially the same I/O performance as the primary storage device in the event a failover occurs. A corresponding system and computer program product are also disclosed and claimed herein.

Abstract: Input/output (I/O) activity in the multiple tier storage system is monitored to collect statistical information. The statistical information is recurrently transformed into an exponential moving average (EMA) of the I/O activity having a predefined smoothing factor. Data portions in the multiple tier storage system are sorted into buckets of varying temperatures corresponding to the EMA. At least one data migration plan is recurrently generated for matching the sorted data portions to at least one of an available plurality of storage device classes. One data portion sorted into a higher temperature bucket is matched with a higher performance storage device class of the available plurality of storage device classes than another data portion sorted into a lower temperature bucket.

Abstract: Provided are a method, system, and computer program product for using information on Input/Output (I/O) sizes of accesses to an extent to determine a type of storage device for the extent from a plurality of storage devices comprising at least one of a first storage type and a second storage type. Performance information is processed for a time period for Input/Output (I/O) operations with respect to an extent maintained in at least one of the storage devices of the first storage type, wherein the performance information indicates an I/O size of the I/O operations with respect to the extent. A determination is made as to whether characteristics of the I/O operations other than I/O size indicate that the extent is eligible for migration to at least one of the storage devices of the second storage type. A determination is made as to whether characteristics of the I/O sizes of the I/O operations.

Abstract: Provided are a computer program product, system and method for managing Input/Output (I/O) requests to a storage device. A write request is received having write data for a logical address in the storage device. A determination is made as to whether preserve mode is enabled. A first entry is located in a volume control table for the logical address indicating a version number of the data in the storage device for the logical address and a first physical location in the storage device having the data for the logical address. The write data is written to a second physical location in the storage device. A second entry is added to the volume control table for the logical address to write in response to determining that the preserve mode is enabled.

Abstract: A method for matching storage application performance in a multiple tier storage system is disclosed. Input/output (I/O) activity in the multiple tier storage system is monitored to collect statistical information. The statistical information is recurrently transformed into an exponential moving average (EMA) of the I/O activity having a predefined smoothing factor. Data portions in the multiple tier storage system are sorted into buckets of varying temperatures corresponding to the EMA. At least one data migration plan is recurrently generated for matching the sorted data portions to at least one of an available plurality of storage device classes. One data portion sorted into a higher temperature bucket is matched with a higher performance storage device class of the available plurality of storage device classes than another data portion sorted into a lower temperature bucket.

Abstract: Provided are a method, system, and computer program product for processing read and write requests in a storage controller. A host adaptor in the storage controller receives a write request from a host system for a storage address in a storage device. The host adaptor sends write information indicating the storage address updated by the write request to a device adaptor in the storage controller. The host adaptor writes the write data to a cache in the storage controller. The device adaptor indicates the storage address indicated in the write information to a modified storage address list stored in the device adaptor, wherein the modified storage address list indicates modified data in the cache for storage addresses in the storage device.

Abstract: A method for allocating space in a cache based on media I/O speed is disclosed herein. In certain embodiments, such a method may include storing, in a read cache, cache entries associated with faster-responding storage devices and cache entries associated with slower-responding storage devices. The method may further include implementing an eviction policy in the read cache. This eviction policy may include demoting, from the read cache, the cache entries of faster-responding storage devices faster than the cache entries of slower-responding storage devices, all other variables being equal. In certain embodiments, the eviction policy may further include demoting, from the read cache, cache entries having a lower read-hit ratio faster than cache entries having a higher read-hit ratio, all other variables being equal. A corresponding computer program product and apparatus are also disclosed and claimed herein.