Different performance indication values for updateDocumentsWithVersionMillis on public documentation

Issue Summary

The accepted average value of updateDocumentsWithVersionMillis statistic is published as 50 MS in https://confluence.atlassian.com/jirakb/troubleshooting-performance-with-jira-stats-1041829254.html and 10 milliseconds on https://confluence.atlassian.com/jirakb/troubleshooting-disk-i-o-bottlenecks-in-jira-data-center-1026550570.html which confusing and makes a big difference when measuring the application's performance.

This is reproducible on Data Center: (yes)

Steps to Reproduce

1. Visit check "Index reads/writes (Lucene)" and "Index Writer Stats Logs (issue stats) (available since Jira 8.10)" on the documents

Expected Results

The value should be common on all documentation or tagged with a specific release if it should change

Actual Results

The administrators and support engineers will be measuring performance against two different values and missing the opportunity to spot/fix the indexing problem.

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available