Redmine

The custom fields list displays the number of projects the issue custom field is used in by doing a database query for each custom field:

custom_field.projects.count

To improve the performance dramatically when there are really lots of issue custom fields the counts should be pre-loaded with a single database query:

@custom_fields_projects_count = IssueCustomField.where(is_for_all: false).joins(:projects).group(:custom_field_id).count

In the view the counts can then be accessed by:

@custom_fields_projects_count[custom_field.id]

A patch file is attached.

Regards,
Thomas