Maintenance of a fabric priority during synchronous copy operations

Patent metadata

Field	Value
Publication number	US-2016357468-A1
Application number	US-201615242374-A
Country	US
Kind code	A1
Filing date	Aug 19, 2016
Priority date	Jun 27, 2014
Publication date	Dec 8, 2016
Grant date	—

Abstract

A primary storage controller receives a write command from a host, wherein Fibre Channel frames corresponding to the write command have a priority indicated by the host. The primary storage controller performs a synchronous copy operation to copy data written by the write command from the primary storage controller to a secondary storage controller, wherein Fibre Channel frames corresponding to the synchronous copy operations have an identical priority to the priority indicated by the host.

First claim

What is claimed is:

1 . A method, comprising:
receiving, by a primary storage controller, a write command from a host, wherein frames corresponding to the write command have a priority indicated by the host; and performing, by the primary storage controller, a synchronous copy operation to copy data written by the write command from the primary storage controller to a secondary storage controller, wherein frames corresponding to the synchronous copy operation have an identical priority to the priority indicated by the host.

2 . The method of claim 1 , wherein, all frames of all related exchanges pairs that satisfy the write command are set to the identical priority corresponding to the priority indicated by the host.

3 . The method of claim 2 , wherein the write command is satisfied by:
a first exchange pair to write the data to the primary storage controller; a second exchange pair to perform the synchronous copy operation; and a third exchange pair to respond from the primary storage controller to the host that the write command is satisfied, wherein: frames of the first exchange pair, the second exchange pair, and the third exchange pair all have the identical priority corresponding to the priority indicated by the host.

4 . The method of claim 2 , the method further comprising:
recording the priority of the write command in an input/output (I/O) task control block maintained in the primary storage controller; and copying the recorded priority to a copy services task control block to transfer the recorded priority for the synchronous copy operation.

5 . The method of claim 2 , wherein:
the primary storage controller and the secondary storage controller control a plurality of storage devices; and a fabric comprising one of more switches couples the primary storage controller, the secondary storage controller and the host.

6 . The method of claim 5 , the method further comprising:
transmitting, by the fabric, the frames corresponding to the write command according to and with the priority indicated by the host to the primary storage controller; and transmitting, by the fabric, the frames corresponding to the synchronous copy operation according to and with the identical priority indicated by the primary storage controller to the secondary storage controller.

7 . A system comprising a primary storage controller, wherein the primary storage controller is coupled to a host and a secondary storage controller, the system comprising:
a memory; and a processor coupled to the memory, wherein the processor performs operations, the operations comprising: receiving, by the primary storage controller, a write command from the host, wherein frames corresponding to the write command have a priority indicated by the host; and performing, by the primary storage controller, a synchronous copy operation to copy data written by the write command from the primary storage controller to the secondary storage controller, wherein frames corresponding to the synchronous copy operation have an identical priority to the priority indicated by the host.

8 . The system of claim 7 , wherein, all frames of all related exchanges pairs that satisfy the write command are set to the identical priority corresponding to the priority indicated by the host.

9 . The system of claim 8 , wherein the write command is satisfied by:
a first exchange pair to write the data to the primary storage controller; a second exchange pair to perform the synchronous copy operation; and a third exchange pair to respond from the primary storage controller to the host that the write command is satisfied, wherein: frames of the first exchange pair, the second exchange pair, and the third exchange pair all have the identical priority corresponding to the priority indicated by the host.

10 . The system of claim 8 , the operations further comprising:
recording the priority of the write command in an input/output (I/O) task control block maintained in the primary storage controller; and copying the recorded priority to a copy services task control block to transfer the recorded priority for the synchronous copy operation.

11 . The system of claim 8 , wherein:
the primary storage controller and the secondary storage controller control a plurality of storage devices; and a fabric comprising one of more switches couples the primary storage controller, the secondary storage controller and the host.

12 . The system of claim 11 , the operations further comprising:
transmitting, by the fabric, the frames corresponding to the write command according to and with the priority indicated by the host to the primary storage controller; and transmitting, by the fabric, the frames corresponding to the synchronous copy operation according to and with the identical priority indicated by the primary storage controller to the secondary storage controller.

13 . A computer program product, comprising:
a computer readable storage medium having computer readable program code embodied therewith, the computer readable program code configured to perform operations on a processor, the operations comprising: receiving, by a primary storage controller, a write command from a host, wherein frames corresponding to the write command have a priority indicated by the host; and performing, by the primary storage controller, a synchronous copy operation to copy data written by the write command from the primary storage controller to a secondary storage controller, wherein frames corresponding to the synchronous copy operation have an identical priority to the priority indicated by the host.

14 . The computer program product of claim 13 , wherein, all frames of all related exchanges pairs that satisfy the write command are set to the identical priority corresponding to the priority indicated by the host.

15 . The computer program product of claim 14 , wherein the write command is satisfied by:
a first exchange pair to write the data to the primary storage controller; a second exchange pair to perform the synchronous copy operation; and a third exchange pair to respond from the primary storage controller to the host that the write command is satisfied, wherein: frames of the first exchange pair, the second exchange pair, and the third exchange pair all have the identical priority corresponding to the priority indicated by the host.

16 . The computer program product of claim 14 , the operations further comprising:
recording the priority of the write command in an input/output (I/O) task control block maintained in the primary storage controller; and copying the recorded priority to a copy services task control block to transfer the recorded priority for the synchronous copy operation.

17 . The computer program product of claim 14 , wherein:
the primary storage controller and the secondary storage controller control a plurality of storage devices; and a fabric comprising one of more switches couples the primary storage controller, the secondary storage controller and the host.

18 . The computer program product of claim 17 , the operations further comprising:
transmitting, by the fabric, the frames corresponding to the write command according to and with the priority indicated by the host to the primary storage controller; and transmitting, by the fabric, the frames corresponding to the synchronous copy operation according to and with the identical priority indicated by the primary storage controller to the secondary storage controller.

Assignees

• IBM

Inventors

• Hathorn Roger G
• Holley Bret W
• Yudenfriend Harry M

Classifications

• G06F16/275

  Synchronous replication · CPC title

• G06F15/167

  using a common memory, e.g. mailbox · CPC title

• G06F3/067

  Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS] · CPC title

• H04L49/00

  Packet switching elements · CPC title

• G06F3/0619 Primary

  in relation to data integrity, e.g. data losses, bit errors · CPC title