Note: The bug mentioned in this article applies to Nexus Repository 2.7+ through to Nexus Repository 2.10.x, although running a Purge Nexus Timeline task is recommended for all versions.
Problem
You are running Nexus Repository 2.7+ through 2.10.x and you notice the size of the directories under ${nexus-work}/timeline are becoming very large. Scheduling a Purge Nexus Timeline task does not seem to help reduce the size of these directories. Nexus performance is becoming sluggish under load, especially during requests which require authentication.
Solution
Upgrade to at least Nexus Repository 2.11 to pick up the fix for NEXUS-7671.
Schedule a Purge Nexus Timeline task with a Purge Items Older Than days value of 30 or less. After the task completes, your timeline directory should contain significantly smaller files and throughput performance should improve.
Alternately, you may choose to completely disable System Feeds should you not wish to make use of this feature.