Posted almost 10 years ago. Visible to the public. Repeats.
MySQL: Disable query cache for database profiling
If you want to see how long your database queries actually take, you need to disable MySQL's query cache. This can be done globally by logging into a database console, run
CopySET GLOBAL query_cache_type=OFF;
and restart your rails server.
You can also disable the cache on a per query basis by saying
CopySELECT SQL_NO_CACHE * FROM ...
You also probably want to disable Rails internal (per-request) cache. For this, wrap your code with a call to ActiveRecord::Base.uncached. For example, as an around_filter:
Copydef disable_cache ActiveRecord::Base.uncached do yield end true end
Don't forget to re-enable MySQL query caching later with
CopySET GLOBAL query_cache_type=ON;
By refactoring problematic code and creating automated tests, makandra can vastly improve the maintainability of your Rails application.
