Importance

Loading Importance Indicators...

Abstract

Two data storage systems are interconnected by a data link for remote mirroring of data. Each volume of data is configured as local, primary in a remotely mirrored volume pair, or secondary in a remotely mirrored volume pair. Normally, a host computer directly accesses either a local or a primary volume, and data written to a primary volume is automatically sent over the data link to a corresponding secondary volume. The host computer sends chains of channel commands to the data storage system containing a primary (R1) volume of a remotely mirrored volume pair. In order to more effectively use the capacity of the data link, the data storage system containing the primary (R1) volume bundles the write data for all write commands in the chain into a single write command for transmission over the data link to the secondary data storage system containing the secondary (R2) volume. The data storage system containing the primary (R1) volume decodes the channel commands to determine when it has received the last channel command in the chain, and once the last channel command in the chain is received, it transmits the bundle of write data for the chain over the data link to the data storage system containing the secondary (R2) volume. In a preferred implementation, the write data is stored in a cache memory in the data storage system containing the primary (R1) volume, and the data storage system containing the primary (R1) volume bundles the write data by accumulating, in a buffer, pointers to the write data in the cache memory.

Loading the Abstract Image...

First Claim