Abstract: A storage device capable of selectively rendering certain data irretrievable is disclosed. The storage device includes Write Once Read Many (WORM) storage medium, a key generator, an encrypted write component, an erasable storage medium and a key deleter. The WORM storage medium is capable of storing data, and the data stored in the WORM data storage medium are unerasable and unrewritable. The key generator provides a generated key that can be stored in the erasable storage medium. The encrypted write component writes a set of sensitive data encrypted by using the generated key to the WORM storage medium. In response to a request for deleting the set of sensitive data from the WORM storage medium, the key deleter deletes the generated key from the erasable storage medium.

Abstract: Write requests from host computers are processed in relation to a thin provisioning storage subsystem. A write request is received from a host computer. The write request identifies a first virtual disk that has been previously assigned to the host computer. It is determined whether the first virtual disk has to be allocated additional physical storage locations of the thin provisioning storage subsystem for storing data associated with the write request. In response to determining that the virtual disk has to be allocated additional physical storage locations, the following is performed. First, a quantity of free space remaining unallocated within physical storage locations of the thin provisioning storage subsystem is determined. Second, where the quantity of free space remaining unallocated within the physical storage locations satisfies a policy threshold associated with a second virtual disk, the second virtual disk is write-inhibited. The first and second virtual disks can be different.

Abstract: A method for migrating data between heterogeneous data storage devices within a storage area network is disclosed. A first virtualizer presents stored data as a first virtual disk, and then communicates a managed disk representation of the first virtual disk to a second virtualizer. After receiving the managed disk representation, the second virtualizer virtualizes the stored data from the managed disk representation as a second virtual disk. At such point, the stored data can be progressively migrated from the first virtualizer to the second virtualizer.

Abstract: A storage network control apparatus is operable to present virtualized storage to a host system and includes a monitoring component, an analysis component, a detection component, and a migration component. The monitoring component is for monitoring input/output (I/O) activity for virtual storage logical units over time. The analysis component is for identifying a repeating instance of peak I/O activity for a virtual storage logical unit over time and for generating a predictive signature therefrom. The detecting component is for identifying an instance of such a predictive signature. The migration component is responsive to the detecting component, and is for migrating data mapped by the virtual storage logical unit across additional real storage units to improve the I/O performance of the virtual storage logical unit prior to a recurrence of the repeating instance of peak I/O activity. A corresponding logic arrangement may be incorporated in hardware, software or a combination thereof.

Abstract: Write requests from host computers are processed in relation to a thin provisioning storage subsystem. A write request is received from a host computer. The write request identifies a first virtual disk that has been previously assigned to the host computer. It is determined whether the first virtual disk has to be allocated additional physical storage locations of the thin provisioning storage subsystem for storing data associated with the write request. In response to determining that the virtual disk has to be allocated additional physical storage locations, the following is performed. First, a quantity of free space remaining unallocated within physical storage locations of the thin provisioning storage subsystem is determined. Second, where the quantity of free space remaining unallocated within the physical storage locations satisfies a policy threshold associated with a second virtual disk, the second virtual disk is write-inhibited. The first and second virtual disks can be different.

Abstract: A storage network control apparatus is operable to present virtualized storage to a host system and includes a monitoring component, an analysis component, a detection component, and a migration component. The monitoring component is for monitoring input/output (I/O) activity for virtual storage logical units over time. The analysis component is for identifying a repeating instance of peak I/O activity for a virtual storage logical unit over time and for generating a predictive signature therefrom. The detecting component is for identifying an instance of such a predictive signature. The migration component is responsive to the detecting component, and is for migrating data mapped by the virtual storage logical unit across additional real storage units to improve the I/O performance of the virtual storage logical unit prior to a recurrence of the repeating instance of peak I/O activity. A corresponding logic arrangement may be incorporated in hardware, software or a combination thereof.

Abstract: A method for migrating data between heterogeneous data storage devices within a storage area network is disclosed. A first virtualizer presents stored data as a first virtual disk, and then communicates a managed disk representation of the first virtual disk to a second virtualizer. After receiving the managed disk representation, the second virtualizer virtualizes the stored data from the managed disk representation as a second virtual disk. At such point, the stored data can be progressively migrated from the first virtualizer to the second virtualizer.

Abstract: A method for migrating data between heterogeneous data storage devices within a storage area network is disclosed. A first virtualizer presents stored data as a first virtual disk, and then communicates a managed disk representation of the first virtual disk to a second virtualizer. After receiving the managed disk representation, the second virtualizer virtualizes the stored data from the managed disk representation as a second virtual disk. At such point, the stored data can be progressively migrated from the first virtualizer to the second virtualizer.

Abstract: A storage network control apparatus is operable to present virtualized storage to a host system and includes a monitoring component, an analysis component, a detection component, and a migration component. The monitoring component is for monitoring input/output (I/O) activity for virtual storage logical units over time. The analysis component is for identifying a repeating instance of peak I/O activity for a virtual storage logical unit over time and for generating a predictive signature therefrom. The detecting component is for identifying an instance of such a predictive signature. The migration component is responsive to the detecting component, and is for migrating data mapped by the virtual storage logical unit across additional real storage units to improve the I/O performance of the virtual storage logical unit prior to a recurrence of the repeating instance of peak I/O activity.

Abstract: A synchronization technique is described which finds use in a disk array subsystem comprising a plurality of disk storage devices connected to a controller. In response to signals from each of the devices specifying their angular position at a particular time, the controller calculates the relative angular positions of the devices and issues a signal to each of the devices specifying the amount and direction of change in rotational velocity required to achieve synchronization. In a two device subsystem, the signal to one device will specify a speed decrease and the signal to the second device will specify a speed increase.

Abstract: A method is described for attaching circuit chips to a flexible substrate (laminate) using controlled chip collapse connection technology (C-4). The substrate is "tinned" with an alloy of eutectic composition in its contact region with the solder balls on the base of the chip. The alloy and the solder are chosen such that they are miscible. The system temperature is raised above the alloy melting point thus causing the alloy and the solder to mix, the mixture composition moving away from the eutectic composition with time and thus raising its melting point. Eventually the mixture melting point is higher than the temperature at which the system is maintained and the mixture solidifies to form a contact. In this way contact between the chip and the flexible substrate can be effected at a temperature below the melting point of the pure solder and lower than one which would result in degradation of the laminate adhesive.