[MNG-3379] Parallel resolution of artifacts

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.0.8
• Fix Version/s: 2.1.0
• Component/s: Artifacts and Repositories
• Flags: Patch
• Assignee: Brett Porter
• Reporter: Donald J. Brown
• Created: 27/Jan/08 04:43
• Updated: 05/Apr/15 14:54
• Resolved: 04/Mar/09 06:47

Description

Artifacts should be resolved in parallel, grouped by group id's to get around the lack of synchronization in the local repository. The patch does the following:

• Use a ThreadPoolExecutor to parallelize artifact resolution, but takes care not to resolve multiple artifacts from the same group id simultaneously. (requires Java 5)
• Makes the http wagon the default instead of the poor performing http-client

Disadvantages:

• Requires Java 5, but the backport jars could be substituted pretty easily
• Breaks some plugins due to commons-logging being in the Maven uber jar (required by commons-httpclient), notably the apt plugin (maybe more should use the isolatedRealm setting?)
• Screws up the progress monitor as multiple threads are updating it

Advantages:

• Much faster when combined with the http wagon (WAGON-98). I was seeing 40% improvement on some test builds.

Issue Links

• is depended upon by: MNG-3004 Allow build lifecycle to execute projects in parallel
• is duplicated by: MNG-3204 Parallel dependency fetching
• is duplicated by: MNG-3739 Perform multiple web requests simultaneously.
• relates to: MNG-4179 [regression] Artifact download hangs upon transfer failure
• relates to: MNG-4432 reimplement parallel artifacts download

Sub-Tasks

• Prominently document opt-out setting for parallel artifact resolution for users: Closed