[FELIX-4656] Improve memory usage and speed of the resolver

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: resolver-1.2.0
• Component/s: Resolver
• Assignee: Guillaume Nodet
• Reporter: Guillaume Nodet
• Created: 27/Sep/14 13:42
• Updated: 16/Oct/15 16:46
• Resolved: 17/Mar/15 09:41

Description

During big resolutions (> 100 bundles), the memory consumption can become very huge, mostly by keeping a lot of copies of the Candidates object.

I want to lower the memory requirements of the resolver without touching the algorithm at all (which would be a different improvement).
This can be done by using :

• lower memory intensive collections
• do smart copies of those collections (where they would only actually copy the data when modify)

The second item is slightly more difficult to achieve, as the maps in the Candidate objects contains Set and List, which would mean that those must be copied too. So it could actually be complementary, if achievable.

For the first one, the HashMap and HashSet are very memory intensive. I'll introduce two new collections which will lower the requirements.

Issue Links

• is duplicated by: FELIX-4819 Use Set instead of List for cycle detection