Abstract: An enhanced mechanism for the allocation, organization and utilization of high performance block storage metadata provides a stream of data (e.g., in a server system, storage system, DASD, etc.) that includes a sequence of fixed-size blocks which together define a page. Each of the fixed-size blocks includes a data block and a footer. A high performance block storage metadata unit associated with the page is created from a confluence of the footers. Each footer in the confluence of footers has space available for application metadata, which are provided as one or more information units. At least one of the footers includes a Checksum field containing a checksum that covers at least the confluence of footers. This approach is advantageous in that it provides data integrity protection, protects against stale data, and significantly increases the amount of metadata space available for application use.

Abstract: A method, apparatus, and computer instructions for controlling data flow. A control message is formed for the data flow in response to an event while the data flow is occurring. The control message includes a data type, an action, and a duration. The control message is sent to a receiver data processing system, wherein the receiver data processing system modifies the data flow to the data processing system using the control message.

Abstract: An enhanced mechanism for the allocation, organization and utilization of high performance block storage metadata provides a stream of data (e.g., in a server system, storage system, DASD, etc.) that includes a sequence of fixed-size blocks which together define a page. Each of the fixed-size blocks includes a data block and a footer. A high performance block storage metadata unit associated with the page is created from a confluence of the footers. Each footer in the confluence of footers has space available for application metadata, which are provided as one or more information units. At least one of the footers includes a Checksum field containing a checksum that covers at least the confluence of footers. This approach is advantageous in that it provides data integrity protection, protects against stale data, and significantly increases the amount of metadata space available for application use.

Abstract: An automatically configurable storage subsystem for use in conjunction with a computer system. The storage subsystem includes a storage controller attached to the computer system and multiple data storage devices which are configurable in multiple diverse arrays. A data transfer parameter is specified by a user which preferably sets forth an estimated average size of a future data transfer and/or an estimated percentage of future sequential data transfers. The data transfer parameter(s) is then coupled to the storage controller and is utilized to automatically configure at least certain of the multiple data storage devices into an appropriate array for future data transfers.