Layout objects are stored in session creating a lot of memory and traffic use

• Type: Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: 6.2.10 EE GA1, 7.0.0 M5
• Fix Version/s: 6.2.4 CE GA5, 6.2.X EE, 7.0.0 M6
• Component/s: Performance
• Labels:
  • 6.1_release_notes
  • backend_test
  • liferay-fixpack-portal-56-6210
• Branch Version/s:
  6.2.x
• Backported to Branch:
  Committed
• Story Points: 8
• Fix Priority: 4
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal/pull/26790

Layout objects are stored in session using the key PREVIOUS_LAYOUT. These objects can get quite heavy, specially properties like:
_embeddedPortlets
_typeSettingsProperties

Steps to reproduce:

1-Sign in
2-Create a page
3-Navigate to that page, then click in "Welcome" again.
4-Go to Control Panel, and execute the attached LPS-54758_reproduce.txt Groovy script, it should show someting like this (XXX is a number that can be too big depending on layout, embedded portlets, etc) :

Previous Layout session object size:XXXX

5-After the fix, execute LPS-54758_fixed.txt as Groovy script in Control Panel, then you should see something like:

Previous Layout session object size:YY

"YY" now it's much less than XXXX and won't grow even when having more embedded portlets or settings on the previous visited page.