Explain deadlock detection and recovery, Database Management System

Assignment Help:

Explain Deadlock detection and recovery

Deadlock Detection - A deadlock is said to take place when there is a circular chain of transaction, every waiting for the release of a data - item held by the next transaction in the chain, the algorithm to detect a deadlock is relies on the detection of such type of a circular chain in the current system in wait - for - graph. The algorithm produces the wait - for - graph at regular intervals and observes it for a chain. The algorithm begins with the assumption that there is no deadlock. 

Deadlock Recovery - To recover from deadlock. The cycles in the wait - for - graph should be broken. The general method of doing this is to roll back one or much more transactions in the cycles till the system shows no further deadlock situation. The procedure of deadlock recovery must make sure that a given transaction is not constantly the one chosen for rollback. The selection of the transaction to be rolled back is relies on the following considerations: 

  • The progress of the transaction and the number of data - items it has employed and modified.
  • The amount of computing lasting for the transaction and the number of data - items that have yet to be accessed through the transaction.
  • The relative cost of rolling back a transaction.

Related Discussions:- Explain deadlock detection and recovery

State in detail about data flow diagram, What is a Data Flow Diagram?  ...

What is a Data Flow Diagram?  Data Flow Diagram: A data flow diagram is the graph that shows flow of data values from their sources in objects in the course of processes whic

Define 2nf normal form, 2NF Normal Form : A relation schema process R i...

2NF Normal Form : A relation schema process R is in 2NF if it is in 1NF and each non-prime attribute A in R is fully functionally related on primary key. Second normal form (2N

Define outer union operation of the relational algebra, Define outer union ...

Define outer union operation of the relational algebra. Compute the outer union for the relations R and S given below. Outer Join - If there are any values in one tabl

Support by adding indexes, Support by Adding Indexes Multiple indexes c...

Support by Adding Indexes Multiple indexes can be used to access a data file by multiple access paths. In such a scheme only single copy of the data is consider, only the numbe

Define the method of recursion, What is recursion? Is it possible for a sto...

What is recursion? Is it possible for a stored procedure to call itself or recursive stored procedure?  How many levels of SP nesting is possible? Recursion is method of proble

Explain the concept of qbe, Explain the concept of QBE? Query-by-exampl...

Explain the concept of QBE? Query-by-example represents a visual/graphical approach for accessing information in a database by the use of query templates called as skeleton tab

What is called a query -execution engine, What is called a query -execution...

What is called a query -execution engine? The query implementation engine takes a query evaluation plan, implements that plan, and returns the answers to the query.

Mention constraints to create command ddl, Mention the type of constraints ...

Mention the type of constraints we can specify in the CREATE command of DDL. The type of constraints that can be specified are as follows:- PRIMARY KEY, NOT NULL, UNIQUE, FOR

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd