Problem

When the JQL search order by "Epic Link" is executed in an environment containing a large number of issues example 2 000 000 issues , Jira does not return a result and the search fails

Finding the values in Lucene

com.atlassian.greenhopper.customfield.epiclink.EpicLinkStatisticsMapper.getValueFromLuceneField(EpicLinkStatisticsMapper.java:61) 

requires also going to the database , and traversing this data will cause long running threads

com.atlassian.jira.ofbiz.WrappingOfBizDelegator.findById(WrappingOfBizDelegator.java:192)
com.atlassian.jira.issue.managers.DefaultIssueManager.getIssue(DefaultIssueManager.java:143) 

Environment

Jira 8 / 9

Steps to Reproduce

Execute the query below without specifying any data limit (date , project, user )

order by "Epic Link"

Expected Results

• Jira will sort all the issues available in the instance by epic link

Actual Results

• Jira's issue table call fails silently and no result is shown on the screen

Workaround

Limit the search result to a smaller data set (by project / by date etc)