LayoutLister can be still slow for very deep structures

• Type: Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: 7.0.0 M3
• Fix Version/s: 6.2.X EE, 7.0.0 M1
• Component/s: Content Publishing > Staging, Core Infrastructure, Performance, Sites Administration > Sites
• Labels:
  • backend_test
  • liferay-fixpack-portal-132-6210
  • performance
• Environment: Tomcat 5 + PostgresSQL 9.1. Portal Master GIT ID: d80818dc84b05302af96832519229a1d95bec6bd.
• Branch Version/s:
  6.2.x
• Backported to Branch:
  Committed
• Fix Priority: 2
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal/pull/16476

Background

Upon investigating a customer issue, I've found three problems in LayoutLister. LPS-36049 enhances its performance, but there are still areas of improvement.

• Method _createList() implements a DFS (Depth First Search) algorithm to traverse the layout tree recursively. As such it isn't feasible for very deep structures.
• Searching for matching layouts based on a parentLayoutId in method createList()_ is done in O(N) complexity.
• The LayoutView object which is created by method getLayoutView() is a good candidate for being cached in a request scoped Thread Local Cache.

With these improvement I could lower the execution time of _createList() (with 5000+ pages) from ~250ms to ~5ms.

Steps to reproduce

1) Create a site called BigSite.
2) Create ~1000 pages: 9 level deep tree, every node has 2 pages and there is one root node. Use attached Groovy script (remember to fill in groupId).
3) Without fix applied: execute attached script (Performance_422995.groovy remember to fill in groupId) multiple times. Write down execution times from the output.

• With fix applied:* execute attached script (Performance_422995_after_fix.groovy remember to fill in groupId) multiple times. Write down execution times from the output.

Executions times before the fix:

Start measuring layouts performance
Total time:35. Number of results:2049

Executions times after the fix (should be lower than before):

Start measuring layouts performance
Total time:16. Number of results:2049