Chances are that if you’re writing Go code for a while now, your needs for command line arguments have grown beyond just what the standard library flag package is able to provide.

With our background jobs interface in place, we can create an API that will queue our incoming data and flush it to the database at a defined frequency. Flushing our data in bulk will give us performance advantages.

API services, especially low latency ones, will resort to background jobs to process data faster on ingesting it, and aggregating and flushing it to backend services in an optimal way.

As we implemented our service that adds pageviews to the database, we realize an unfortunate circumstance. Each insert query takes about 12ms, which means our request rate, at least per single CPU core, is poor. We’re talking about 83 req/s poor.

After we set up Elastic APM to log our request transaction, the following thing we wish to instrument are the SQL queries going to our database endpoint. Elastic APM provides instrumentation that wraps the database/sql driver, which produces an *sql.DB.

Elastic APM is an application performance monitoring product Elastic, the makers of Elasticsearch, and most notably the ELK stack (Elasticsearch, Logstash, Kibana). APM is another plug and play product of theirs, that hooks up to your existing ELK installation and provides endpoints for application agents to receive performance metrics data.