Redmine The custom field grows slower

After the Redmine deployment was used, it was found that updating transactions was slow, related experiments were made, and the plug-ins that could affect speed were removed, still slow. The following is a comparison test:

1. Items with 12 custom fields, updated with 2136ms, are recorded as follows:

Started PATCH "/issues/3115" for 127.0.0.1 at 2016-07-03 10:58:36 +0800
Processing by Issuescontroller#update as HTML
Parameters: {"UTF8" + "?", "Authenticity_token" = "qnzr0iqhr6x6otexs0d0w9b+2fwma/ 0yfiuoskbmgsqymlb7lwqzjlb19gqanwsjh/6iubuif4l1x+e6ne8vhq== "," form_update_triggered_by "=" "," issue "=>{" project_id "=" 5 "," tracker_id "and" 5 "," Subject "and" XX Project "," description "and" XX Project "," status_id "and" 6 "," priority_id "+" 4 "," Custom_field_values "=>{", "" and "", "" and "XX", "the" "and" "," "and" "," "and" "," and "xx "," "" "" and "2016-05-18", "2016-05-18" and "2016-07-12", "Wuyi" "=", "0", "3" and "2016-05-18", "23" = > "," "" "" "", "" "}," Notes "=" "," Lock_version "and" 0 "}," Was_default_status "and" 6 "," last_journal_id "and" = " "", "commit" and "submit", "next_issue_id" and "3114", "Issue_position" and "1", "Issue_count" and "Max", "id" and "=" 3115 "}
Current USER:CSL (id=26)
Rendered Mailer/_issue.text.erb (15.6MS)
Rendered Mailer/issue_edit.text.erb within Layouts/mailer (31.2ms)
Rendered Mailer/_issue.html.erb (0.0ms)
Rendered Mailer/issue_edit.html.erb within Layouts/mailer (0.0ms)
Redirected to Http://127.0.0.1:8080/issues/3115?issue_count=150&issue_position=1&next_issue_id=3114
Completed 302 Found in 2136ms (activerecord:115.6ms)

2. Items with 51 custom fields, updated with 5745ms, are recorded as follows:

Started PATCH "/issues/3890" for 127.0.0.1 at 2016-07-03 10:57:07 +0800
Processing by Issuescontroller#update as HTML
Parameters: {"UTF8" + "?", "Authenticity_token" = "bdb8/sffgd0ltt45nvqpa/dquk/s/nexrrr0/ oredstdnp1wpobgte8cheigibljpmopa/+1u6bnwbt2ug07ig== "," form_update_triggered_by "=" "," issue "=>{" status_id "= 2", "priority_id" and "2", "assigned_to_id" and "" "," start_date "and" "," Due_date "and" "," custom_field_ Values "=>{" "" and "", "" "" and "" XXX "," All "and" "," "" and "", "" "and" "," 3 "and" "", "" "and" " , "Panax Notoginseng" and "0", "All" and "" "," "" and "" "," "and" "0", "" "and" "", "" "" and "", "" "and" "," "" "," "" " , "" "and" "", "" "and" ""}, "Notes" = "", "Lock_version" and "3"}, "last_journal_id" and "246", "commit" and "submit" , "prev_issue_id" and "3904", "next_issue_id" and "3883", "Issue_position" and "2", "Issue_count" and "+", "id" = > "3890"}
Current USER:CSL (id=26)
Rendered Mailer/_issue.text.erb (31.2ms)
Rendered Mailer/issue_edit.text.erb within Layouts/mailer (93.6ms)
Rendered Mailer/_issue.html.erb (15.6MS)
Rendered Mailer/issue_edit.html.erb within Layouts/mailer (15.6ms)
Rendered Mailer/_issue.text.erb (15.6MS)
Rendered Mailer/issue_edit.text.erb within Layouts/mailer (31.2ms)
Rendered Mailer/_issue.html.erb (0.0ms)
Rendered Mailer/issue_edit.html.erb within Layouts/mailer (15.6ms)
Redirected to http://127.0.0.1:8080/issues/3890?issue_count=15&issue_position=2&next_issue_id=3883& prev_issue_id=3904
Completed 302 Found in 5745ms (activerecord:66.8ms)

Initially, the workaround is to reduce the custom field of the tracking label.

Redmine The custom field grows slower