Synchronous input/output replication of data in a persistent storage control unit

Patent metadata

Field	Value
Publication number	US-10068001-B2
Application number	US-201615181548-A
Country	US
Kind code	B2
Filing date	Jun 14, 2016
Priority date	Oct 1, 2015
Publication date	Sep 4, 2018
Grant date	Sep 4, 2018

Abstract

Aspects include synchronous input/output (I/O) replication of data. A synchronous I/O request is received from an operating system (OS) by firmware on a server. A plurality of synchronous I/O mailbox commands is transmitted by the firmware to a plurality of persistent storage control unit (SCU) nodes. The content of each of the plurality of synchronous I/O commands is based on the synchronous I/O request. A unit of work in the OS corresponding to the synchronous I/O request remains active at least until the synchronous I/O request is completed. It is determined, by the firmware, that determining that each of the plurality of persistent SCU nodes have completed their respective synchronous I/O commands. Based on the determining, the firmware indicates to the OS that the synchronous I/O request is completed.

First claim

What is claimed is:

1. A method comprising:
performing synchronous input/output (I/O) replication of data in a plurality of persistent storage control unit (SCU) nodes, the performing comprising
receiving, by firmware on a server from an operating system (OS) executing on the server, a synchronous I/O request;
transmitting, by the firmware, a plurality of synchronous I/O mailbox commands to a plurality of persistent storage control unit (SCU) nodes, content of each of the plurality of synchronous I/O commands is based on the synchronous I/O request, and a unit of work in the OS corresponding to the synchronous I/O request remains active at least until the synchronous I/O request is completed;
determining, by the firmware, that each of the plurality of persistent SCU nodes have completed their respective synchronous I/O commands; and
based on the determining, indicating, by the firmware, to the OS that the synchronous I/O request is completed,

wherein the transmitting is via one or more write operations using a low latency protocol to communicate directly between the server and each of the plurality of persistent SCU nodes.

2. The method of claim 1 , wherein the synchronous I/O request is a write request.

3. The method of claim 2 , wherein a data record specified by the write request is written to each of the plurality of persistent SCUs nodes.

4. The method of claim 1 , wherein the plurality of synchronous I/O commands is two synchronous I/O commands and the plurality of persistent SCU nodes is two persistent SCU nodes.

5. The method of claim 1 , wherein the plurality of synchronous nodes process their respective synchronous I/O commands independently of each other.

6. The method of claim 1 , wherein the low latency protocol a peripheral component interconnect express (PCIe) protocol.

Assignees

• IBM

Inventors

• Craddock David F
• Glendening Beth A
• Kalos Matthew J
• Sutton Peter G
• Yudenfriend Harry M

Classifications

• H04L67/1095

  Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes · CPC title

• H04L67/1097

  for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS] · CPC title

• G06F13/4282

  on a serial bus, e.g. I2C bus, SPI bus (on daisy chain buses G06F13/4247) · CPC title

• G06F13/4221

  being an input/output bus, e.g. ISA bus, EISA bus, PCI bus, SCSI bus · CPC title

• G06F16/275 Primary

  Synchronous replication · CPC title