Method for enhancing performance of a RAID 1 read operation using a pair of I/O command blocks in a chain structure
US5758187A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 15, 1996 |
| Grant date | May 26, 1998 |
| Priority date | — |
| Expiry date | Mar 15, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F13/126
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An I/O command block, that is stored in a memory, includes information for connecting the I/O command block to other I/O command blocks in a chain structure. The I/O command block chain structure allows simultaneity of execution, provides a mechanism to inhibit and enable execution of an individual I/O command block, and a mechanism for establishing precedence in the sequence of execution of the I/O command blocks. This level of capability is provided by only information in the I/O command blocks within the chain. To enhance a RAID 1 read operation, a pair of killer I/O command blocks for the RAID 1 read operation are built in a chain. Each of the killer I/O command blocks includes a read command for a target device. The pair of killer I/O command blocks are enabled concurrently for execution. During execution, one of the pair of killer I/O commands marked for abortion by the other of the pair of killer I/O commands upon the other of the pair of killer I/O commands initiating data transfer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.