what is an iDB protocol

Source : http://www.dbaleet.org 

There may have heard of the agreement the ZDP and IDB agreement, two new term, if there is a better understanding that this is a long time wine in new bottles. iDB protocol is used for the the Exadata database node (DB node) and the storage node (cell node) communication between. it represents intelligence, again revealing one intelligent database protocol, you can do not look down on it, the essence of the entire Exadata offloading depend on it to complete, the reason one machine only other third-party Oracle Database Exadata shape Exadata God The reason for this. It is implemented by the Oracle database kernel, the smart will table scan work put into the end to finish, and then filtered by the storage, the last returns only the data needed by the query. For a simple example: for example, a table of 100 million lines, but to meet the filter criteria only 10,000 lines of database node will issue a directive tells the storage node, "I need to check a certain table filter conditions, you go deal with the results told I'd be, I have other things to be busy. " This command is iDB. The iDB implementation of Oracle Corporation's top secret, no one knows how internal in addition to the the Exadata core R & D team and technology executives only know the the iDB protocol is running in the above the ZDP agreement (Zero-loss Zero-copy Datagram Protocol) , V3 version (OFED version 1.3.1)), based on the RDS protocol-based standards for research and development. Oracle official data show that use the ZDP protocol for data transmission can achieve per second 3GB / s, but only 2% of the resources of the host CPU consumption.

RDS protocol:

Reliable Datagram Sockets (RDS) is actually developed by Oracle running on the infiniband top, directly based on the agreement of the IPC. The reason for such a protocol, the fundamental reason is that the traditional TCP / IP stack itself is too inefficient, too expensive high-speed Internet, leading to low transmission efficiency. RDS compared IPoIB CPU consumption reduced by 50%, compared with traditional UDP protocol, network delay reduced by half. Topology diagram of the left side of the following figure infiniband IPoIB protocol equipment, the right side is the infiniband devices using the RDS protocol topology. By default, RDS protocol will not be used to take additional measures to relink. Another even relink RDS library CSS communication between the RAC node is unable to use the RDS protocol, maintenance and monitoring of heartbeat between nodes always use IPoIB. The use of the left side of the following figure infiniband IPoIB protocol topology, the right side of the RDS protocol infiband topology.