Tuesday, August 23, 2005

SimpleDBM's Transaction Manager

This week I am working on the Transaction Manager for SimpleDBM. The Transaction Manager is based upon the well known algorithm known as ARIES. There is a freely available paper at ARIES inventor C.Mohan's website that describes ARIES in quite a lot of detail.

I wrote a short description of ARIES, which can be found at Apache Derby website.

ARIES is based upon the recovery algorithms used in IBM's original Database 2 (DB2) product. A good description of the DB2 recovery method can be found in the paper Data Recovery in IBM Database 2, by R.A.Crus. The main contribution of ARIES is that during system restart, failed transactions are also redone, as opposed to redoing only active/committed transactions. This simplifies the subsequent recovery.

No comments: