TransitioningAttributeStorage and the sonatype-work/nexus/proxy directory

Visit my.sonatype.com for documentation on Nexus Repository version 2.

This article only applies to Nexus Repository 2.0 to 2.7. Nexus Repository 2.8+ need not apply the suggestions here.

Improve Performance Disabling Old Attribute Storage

If your Nexus Repository 2 still has a sonatype-work/nexus/proxy directory and this directory contains a readme.txt file, please follow these steps:

1. Stop Nexus Repository 2
2. Delete sonatype-work/nexus/proxy
3. Start Nexus Repository 2

Explanation

In Nexus Repository versions before 2.0, artifact metadata was stored in the sonatype-work/nexus/proxy directory. This directory contained a sub-directory per repository id. Each repository directory contained files at paths matching a real artifact path stored under sonatype-work/nexus/storage. These "attribute" files contained XML metadata about the artifact file such as when the artifact was last accessed and who uploaded the artifact.

Nexus Repository 2.0 introduced an improved attribute storage mechanism. On upgrade from a work directory containing the "proxy" directory, a background thread will upgrade the old attribute storage, putting attributes under sonatype-work/nexus/storage/<repository_id>/.nexus/attributes. Once the upgrade process is complete, Nexus Repository 2 will put a readme.txt file in the proxy directory, indicating the attribute storage upgrade is complete to a new format.