Slow load speed for page using Page Properties Macro report - regression

Summary

Load time for pages with page properties macro report will be significantly degraded after upgrade to Confluence 6.8.1.
If pages have external gadgets load time will be even slower.

Environment

• Confluence 6.8.1

Steps to Reproduce

1. Create 200 pages with page properties macro
2. Create single page with page properties report macro.
3. Load page

Expected Results

Page initial request will load in less then 1s (local test 0.2s). And page in less then ~10sec.

Actual Results

100 pages:

200 pages:

Notes

Issue was not present in Confluence 6.5.1

Bug affects these libraries:
confluence-masterdetail-plugin-parent-5.1.0
confluence-masterdetail-plugin-parent-5.1.1

Workaround

In some cases, disabling external gadgets can help in load time.

One way to workaround is obtain  com/atlassian/confluence/macro/macro-asyncsafe-whitelist.properties file (extracting it from confluence.jar) and then adding bottom line to the file. Then copy the file into <installation-directory>/confluence/WEB-INF/classes/com/atlassian/confluence/macro/macro-asyncsafe-whitelist.properties

detailssummary=true

Then restart of Confluence (see https://confluence.atlassian.com/doc/installing-patched-class-files-166528493.html)

For reference file macro-asyncsafe-whitelist.properties is attached to the ticket.