International Business Machines Corporation

Ibm Canada Limited - Ibm Canada Limitee

Joseph Serge Limoges

Dominique Jeremy Evans

Matthew Albert Huras

Mark Francis Wilding

Timothy Jon Vincent

William T O'Connell

Robert Alan Begg

Klaus B Schiefer

Mario S Godinez

Stephen A Schormann

Dominque J Evans

Russell M Stocker

Dale J Hagen

Dominique J Evans

A method, computer program product and computing device for promoting reuse of previously generated access plans are disclosed. SQL statements containing literals are amended so as to substitute a parameter marker for each literal. Amended statements are provided to the DBMS along with parameters including the substituted literals and a substitution indicator indicating that the substitution has been performed. The DBMS assesses the soundness of the substitutions that are performed. Soundness may be measured in terms of the semantic correctness of the amended statement and the likelihood that the literal substitution will improve DBMS efficiency. If a substitution is unsound, the DBMS may obtain and optimize the original version of the amended SQL statement. Otherwise, the amended statement is optimized. Advantageously, SQL statements originally differing only in the value of one or more literals may become functionally equivalent, and the reuse of cached, previously generated access plans is thus promoted.

Substituting parameter markers for literals in database query language statement to promote reuse of previously generated access plans

A method and database management system for connecting to a database involves reusing connections for operations performed in sequence, rather than creating independent connections for each requested client connection. An application server, or layer, receives the requests and parses them to identify modes of operation. Separate connections are created to support each mode of operation so that the database receives the operations and requests in a format that is sorted by type, at a rate that can be adjusted to match capacity of the database.

System and method for accessing resources in a database

A spin counter updating system and method for updating spin counters for spin latches in a multiprocessor computing system. The updating system includes main spin counter value storage for storing spin counter data correlated to at least one spin counter value, and a master agent. The master agent includes agent spin counter value storage for storing spin counter data correlated to at least one spin counter value; and a spin counter signal handler, wherein the spin counter signal handler is adapted to read spin counter data from the main spin counter value storage and to store the read spin counter data to the agent spin counter value storage.

Updating spin counters for spin latches

An adaptive spin latch system is provided for use in a multiprocessor computer system. The spin latch system includes a run queue, a spin latch module and a wait queue. The run queue is adapted to store agent index data correlated to at least one agent in run mode. The spin latch module is adapted to put the at least one agent into sleep mode for a period of time correlated to a number of agents awaiting access to a resource. The wait queue is adapted to store agent index data correlated to the at least one agent in sleep mode. A method of regulating access by agents to a resource in a multiprocessor computing system is also provided.

Adaptive spin latches

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Etobicoke, Canada

Joseph Serge Limoges