Data copy between peer-to-peer controllers

A method of copying data sets from a first storage device to a second storage device, wherein the first storage device is managed by a first controller and the second storage device is managed by a second controller, comprising of:

• receiving a command with the first controller to copy a range of sequential data sets from the first storage device to the second storage device;
• generating a first data structure comprising:
• (i) generating a first field indicating a location in the first storage device of the first data set in the sequence;
• and
• (ii) generating a pointer indicating a data set in the first extent to copy from the first storage device to the second storage device, wherein the first controller processes the first field and pointer to determine a data set to copy to the second controller, and wherein the pointer is incremented after transferring the copy of the data set to the second controller;
• and
• generating a second data structure comprising:
• (i) generating a first field indicating a location in the second storage device of where to store the first data set in the sequence;
• and
• (ii) generating a pointer indicating a location in the second storage device to store data received from the first storage device, wherein the second controller processes the first field and pointer to determine the location in the second storage device where to store the data set received from the first controller, and wherein the pointer is incremented after storing the data set in the second storage device;
• for the data sets subject to the command, performing:
• (i) transferring a copy of the data set from the first controller to the second controller;
• (ii) storing with the second controller the copy of the data set received from the first controller in the second storage device;
• (iii) modifying the field in the first data structure corresponding to the data set copied to the second storage device to indicate that the data set was copied to the second storage device;
• and
• (iv) modifying the field in the second data structure corresponding to the data set the second controller stores in the second storage device to indicate that the data set was stored in the second storage device.

A system for copying data sets, comprising:

• a first controller;
• a first storage device managed by the first controller capable of storing data sets;
• a second controller;
• a second storage device managed by the second storage controller capable of storing data sets;
• a network communication line providing data communication between the first controller and the second controller;
• a first memory device for storing data for access by the first controller, including a first data structure stored in the first memory device, wherein the first data structure includes fields corresponding to the data sets, wherein the data fields indicate whether the data sets were copied from the first storage device to the second storage device, and wherein the first controller processes the first data structure to determine whether a data set was copied from the first storage device to the second storage device;
• and
• a second memory device for storing data for access by the first controller, including a second data structure stored in the second memory device, wherein the second data structure includes fields corresponding to the data sets, wherein the data fields indicate whether the data sets were copied from the first storage device to the second storage device, and wherein the second controller processes the second data structure to determine whether a data set was copied from the first storage device to the second storage device,
• wherein the first controller generates the first data structure and modifies the first data structure, and wherein the second controller generates the second data structure and modifies the second data structure.

A system for copying data sets, comprising:

• a first controller;
• a first storage device managed by the first controller capable of storing data sets;
• a second controller;
• a second storage device managed by the second storage controller capable of storing data sets;
• a network communication line providing data communication between the first controller and the second controller;
• a first memory device for storing data for access by the first controller, including a first data structure stored in the first memory device, wherein the first data structure includes fields corresponding to the data sets, wherein the data fields indicate whether sequential data sets were copied from the first storage device to the second storage device, and wherein the first controller processes the first data structure to determine whether a data set from sequential data sets was copied from the first storage device to the second storage device;
• and
• a second memory device for storing data for access by the first controller, including a second data structure stored in the second memory device, wherein the second data structure includes fields corresponding to the data sets, wherein the data fields indicate whether the sequential data sets were copied from the first storage device to the second storage device, and wherein the second controller processes the second data structure to determine whether a data set from, sequential data sets was copied from the first storage device to the second storage device;
• wherein the first data structure stored in the first memory includes:
• (i) a first field indicating a location in the first storage device of the first data set in the sequence;
• (ii) a pointer indicating a data set in the first extent to copy from the first storage device to the second storage device, wherein the first controller processes the first field and pointer to determine a data set to copy to the second controller, and wherein the pointer is incremented after transferring the copy of the data set to the second controller;
• and
• wherein the second data structure stored in the second memory includes:
• (i) a first field indicating a location in the second storage device of where to store the first data set in the sequence;
• and
• (ii) a pointer indicating a location in the second storage device of where to store data received from the first storage device, wherein the second controller processes the first field and pointer to determine the location in the second storage device of where to store the data set received from the first controller, and wherein the pointer is incremented after storing the data set in the second storage device.

A first memory and second memory for storing data for access by a first controller and second controller, wherein the first controller processes data in the first memory to copy data sets from a first storage device to the second controller, and wherein the second controller processes data in the second memory to store data sets received from the first controller in a second storage device, comprising:

• a first data structure stored in the first memory, including addressable locations corresponding to the data sets, wherein the addressable locations indicate whether the data sets were copied from the first storage device to the second storage device, and wherein the first controller processes the first data structure to determine whether a data set was copied from the first storage device to the second storage device;
• and
• a second data structure stored in the second memory, including addressable locations corresponding to the data sets, wherein the addressable locations indicate whether the data sets were copied from the first storage device to the second storage device, and wherein the second controller processes the second data structure to determine whether a data set was copied from the first storage device to the second storage device,
• wherein the first controller generates the first data structure and modifies the first data structure, and wherein the second controller generates the second data structure and modifies the second data structure.

A first memory and second memory for storing data for access by a first controller and second controller, wherein the first controller processes data in the first memory to copy sequential data sets from a first storage device to the second controller, and wherein the second controller processes data in the second memory to store the sequential data sets received from the first controller in a second storage device, comprising:

• a first data structure stored in the first memory including addressable locations corresponding to the data sets, wherein the addressable locations indicate whether the data sets were copied from the first storage device to the second storage device, wherein the first controller processes the first data structure to determine whether a data set was copied from the first storage device to the second storage device, and further including:
• (i) a first field indicating a location in the first storage device of the first data set in the sequence;
• (ii) a pointer indicating a data set in the first extent to copy from the first storage device to the second storage device, wherein the first controller processes the first field and pointer to determine a data set to copy to the second controller, and wherein the pointer is incremented after transferring the copy of the data set to the second controller;
• and
• a second data structure stored in the second memory, including addressable locations corresponding to the data sets, wherein the addressable locations indicate whether the sequential data sets were copied from the first storage device to the second storage device, wherein the second controller processes the second data structure to determine whether a data set was copied from the first storage device to the second storage device, and further including:
• (i) a first field indicating a location in the second storage device of where to store the first data set in the sequence;
• and
• (ii) a pointer indicating a location in the second storage device of where to store data received from the first storage device, wherein the second controller processes the first field and pointer to determine the location in the second storage device of where to store the data set received from the first controller, and wherein the pointer is incremented after storing the data set in the second storage device.

Code implemented in a computer readable medium for causing a first and second controllers to copy data sets from a first storage device to a second storage device, wherein the first storage device is managed by the first controller and the second storage device is managed by the second controller, wherein the code is capable of causing at least one of the first controller and second controllers to perform:

• receiving a command with the first controller to copy a plurality of data sets from the first storage device to the second storage device;
• generating first and second data structures including fields corresponding to the data sets and indicating in the fields that the data sets have not been copied;
• and
• for the data sets subject to the command, performing:
• (i) transferring a copy of the data set from the first controller to the second controller;
• (ii) storing with the second controller the copy of the data set received from the first controller in the second storage device;
• (iii) modifying the field in the first data structure corresponding to the data set copied to the second storage device to indicate that the data set was copied to the second storage device;
• and
• (iv) modifying the field in the second data structure corresponding to the data set the second controller stores in the second storage device to indicate that the data set was stored in the second storage device,
• wherein the first controller generates the first data structure and modifies the first data structure, and wherein the second controller generates the second data structure and modifies the second data structure.

Code implemented in a computer readable medium for causing a first and second controllers to copy data sets from a first storage device to a second storage device, wherein the first storage device is managed by the first controller and the second storage device is managed by the second controller, wherein the code is further capable of causing at least one of the first controller and second controllers to perform:

• receiving a command with the first controller to copy a range of sequential data sets from the first storage device to the second storage device;
• generating a first data structure comprising:
• (i) generating a first field indicating a location in the first storage device of the first data set in the sequence;
• and
• (ii) generating a pointer indicating a data set in the first extent to copy from the first storage device to the second storage device, wherein the first controller processes the first field and pointer to determine a data set to copy to the second controller, and wherein the pointer is incremented after transferring the copy of the data set to the second controller;
• and
• generating a second data structure comprising:
• (i) generating a first field indicating a location in the second storage device of where to store the first data set in the sequence;
• and
• (ii) generating a pointer indicating a location in the second storage device to store data received from the first storage device, wherein the second controller processes the first field and pointer to determine the location in the second storage device where to store the data set received from the first controller, and wherein the pointer is incremented after storing the data set in the second storage device;
• for the data sets subject to the command, performing:
• (i) transferring a copy of the data set from the first controller to the second controller;
• (ii) storing with the second controller the copy of the data set received from the first controller in the second storage device;
• (iii) modifying the field in the first data structure corresponding to the data set copied to the second storage device to indicate that the data set was copied to the second storage device;
• and
• (iv) modifying the field in the second data structure corresponding to the data set the second controller stores in the second storage device to indicate that the data set was stored in the second storage device.