Method and apparatus for round trip synchronous replication using SCSI reads
US8738813B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 27, 2011 |
| Grant date | May 27, 2014 |
| Priority date | — |
| Expiry date | May 31, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F11/1471
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The SCSI WRITE command is a two round trip protocol, which introduces significant latency in synchronous replication environments. Example embodiments of the present invention overcome these and other deficiencies by using SCSI READ commands from the replication site to the production site instead of using SCSI WRITE commands from the production site to the replication site to decrease latency in a synchronous replication environment. SCSI READ commands are single round trip commands. Thus, the number of round trips required to complete each I/O is reduced from two round trips to one round trip by maintaining at least one SCSI READ command from a SCSI initiator to a SCSI target and then responding to at least one of the at least one SCSI READ command at the SCSI target according to the SCSI READ command.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.