Design

Introduction

This document contains design changes (from the thesis design to the next version).

Root

Use prefix-number to avoid ever overwriting (eliminates need for atomic write). During recover, a search starting from 0 is used to find the newest root. Garbage-collection may remove deprecated roots from beneath.

External and local databases

Split the databases used (KeyIndex and HashIndex) to something simple locally, and convert these to something content-specific before transfer.

HashIndex

Use a delta-patch as the external format. During recovery, delta patches are stitched together until a full version is found.

KeyIndex

Use a combination of a b-tree and a suffix-tree to provide a layout designed for sharing of sub-trees.