Recent posts

Preventing lock of table during migration using LHM (Large Hadron Migrator)

Problem definition

Running migration which adds column to a table which has a couple million of records may be problematic, because of lock of this table during migration. Let’s say it not only may be problematic - it was problematic, because of this problem our server was down for a couple of minutes and SQL server was restarted, so to solve this problem we using ‘LHM’ gem - Large Hadron Migrator

Cache expiration by custom fields

I recently worked on the performance issue, which was solved by caching and I will describe below example of the solution which I came to.