Dell Products Inc.

Oracle International Corporation

Saikrishnan Krishnamurthy

William Edward Snaman, Jr

Mitchell Condylis

In some embodiments, a client replication service manages log mining during a rolling upgrade, in which the primary role is switched over from an original primary DBMS to a new primary DBMS having updated software. The client replication service or specifically a mining engine maintains an original session on the original primary DBMS to mine redo logs associated with the original primary DBMS until the original primary DBMS is not a primary DBMS anymore. At that time, if the mining of those redo logs is not complete, the client replication service further starts a downstream session on the new primary DBMS to mine copies of the unmined redo logs.

Redo mining during rolling upgrade

A deferred mechanism of rolling attribute changes to objects at transaction commit time is described. To support rolling updates, attributes are categorized into three types&#x2014;increment, decrement or replace. Since transactions are committed in order, the update process uses a notification list of dependent transactions to propagate attribute changes as a function of attribute category or type. Shadow based file-systems (with or without object versioning) realize efficiency gains by employing the deferred mechanism.

Updating object attributes in a lock-coupled namespace traversal

Highly concurrent systems use lock-coupling for tree traversal wherein only two levels (parent and current) are locked at any time. The parent lock is released as soon as successful lock is attained on the grandchild. The rename technique described here facilitates using finer grained locking and multiple path traversals by changing lock ownerships.

Growing community of inventors

Nashua, NH, United States of America

Saikrishnan Krishnamurthy