Abstract: Provided are a computer program product, system, and method for providing access information to a storage controller to determine a storage tier for storing data. Access information is maintained for each data record in a data store, wherein the access information indicates a level of access to each data record in the data store. A write request directed to a data record in the data store is received. A command is generated identifying the data record and including the access information for the data record. The command is transmitted to the storage controller, wherein the storage controller uses the access information to determine one of the plurality of storage tiers on which to store the data record.

Abstract: Provided are a computer program product, system, and method for providing access information to a storage controller to determine a storage tier for storing data. Access information is maintained for each data record in a data store, wherein the access information indicates a level of access to each data record in the data store. A write request directed to a data record in the data store is received. A command is generated identifying the data record and including the access information for the data record. The command is transmitted to the storage controller, wherein the storage controller uses the access information to determine one of the plurality of storage tiers on which to store the data record.

Abstract: Methods and arrangements for selecting a migration decision window for hotspots in a multi-tier enterprise storage system. Aspects include collecting usage statistics for data stored in the multi-tier enterprise storage system, identifying hotspots from data stored in the multi-tier enterprise storage system based on the usage statistics, and determining one or more characteristics of the identified hotspots. Aspects further include calculating an average lifespan of the identified hotspots based on the one or more characteristics of the identified hotspots and selecting the migration decision window based on the average lifespan of the identified hotspots and the one or more characteristics of the identified hotspots.

Abstract: An application server can be configured to access data stored on a networked storage server that is accessible over a network and that includes a cache device configured to store data received from the networked storage server. The application server can include a cache management module that is designed to monitor a data access requests transmitted over the network, the data access requests specifying a first page of data. In response to an indication that the requested data includes data stored in the cache device as an existing page of data, the first page of data can be mapped to a location corresponding to the existing page.

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.

Abstract: A storage controller receives hints provided by one or more applications over a period of time, wherein the hints are used by the storage controller for organizing data in storage managed by the storage controller. Data on conflicts caused by the provided hints are collected over the period of time. Based on the collected data on the conflicts, one or more conflict avoidance rules are executed to reduce possibility of future conflicts.

Abstract: A method for organizing data at levels of granularity larger or smaller than an extent is disclosed. The method initially closes a dataset on a host system. The host system includes a mapping table storing a logical address of the dataset. When the dataset is closed, the host system generates a message indicating that the dataset has been closed and sends the message to a storage system storing the dataset. In response, the storage system allocates a new logical address and copies the dataset from the existing logical address to the new logical address to improve data placement. The storage system then returns the new logical address to the host system so that the host system can update its mapping table. A corresponding system and computer program product are also disclosed.

Abstract: A computer program product, system, and method for managing metadata for caching devices during shutdown and restart procedures. Fragment metadata for each fragment of data from the storage server stored in the cache device is generated. The fragment metadata is written to at least one chunk of storage in the cache device in a metadata directory in the cache device. For each of the at least one chunk in the cache device to which the fragment metadata is written, chunk metadata is generated for the chunk and writing the generated chunk metadata to the metadata directory in the cache device. Header metadata having information on access of the storage server is written to the metadata directory in the cache device. The written header metadata, chunk metadata, and fragment metadata are used to validate the metadata directory and the fragment data in the cache device during a restart operation.

Abstract: In accordance with one aspect of the present description, in response to a detection by a storage controller, of an operation by a host relating to migration of input/output operations from one host to another, a cache server of a storage controller, transmits to a target cache client of the target host, a cache map of the source cache of the source host wherein the cache map identifies locations of a portion of the storage cached in the source cache. In response, the cache client of the target host, may populate the target cache of the target host with data from the locations of the portion of the storage, as identified by the cache map transmitted by the cache server, which may reduce cache warming time. Other features or advantages may be realized in addition to or instead of those described herein, depending upon the particular application.

Abstract: A computer program product, system, and method for managing metadata for caching devices during shutdown and restart procedures. Fragment metadata for each fragment of data from the storage server stored in the cache device is generated. The fragment metadata is written to at least one chunk of storage in the cache device in a metadata directory in the cache device. For each of the at least one chunk in the cache device to which the fragment metadata is written, chunk metadata is generated for the chunk and writing the generated chunk metadata to the metadata directory in the cache device. Header metadata having information on access of the storage server is written to the metadata directory in the cache device. The written header metadata, chunk metadata, and fragment metadata are used to validate the metadata directory and the fragment data in the cache device during a restart operation.

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.

Abstract: Provided are a computer program product, system, and method for an application to provide data attributes to a storage manager to use to select a storage tier to use for a data set management operation. Each storage tier has storage devices with different storage attributes. The storage manager receives information on data attributes for one of the data sets for which a data set management operation is to be performed for an application, wherein the data attributes are based on the application intended usage of the data set and receives a data set management command to perform the data set management operation. The storage manager selects one of the storage tiers having storage attributes that map to the data attributes and performs the data set management operation with respect to the selected storage tier.

Abstract: Provided are a computer program product, system, and method for an application to provide data attributes to a storage manager to use to select a storage tier to use for a data set management operation. Each storage tier has storage devices with different storage attributes. The application determines data attributes of a data set for which a data set management operation is to be performed based on an application intended usage of the data set. The application sends the determined data attributes and a data set management command to the storage controller to cause the storage controller to use the determined data attributes to select one of the storage tiers of storage devices for performing the data set management operation specified by the data set management command.

Abstract: An optimal lease period of data is determined for each client by a centralized entity by using a variety of factors. The variety of factors include at least access characteristics of the data, historical access patterns of the data, and system configurations and policies.

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: 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: 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.

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.

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.