An Ideal Structure Doesn't Guarantee Fast Performance

SSG.COM's promotional event service is a feature that curates and displays products according to a specific theme. A single promotional event has multiple classifiers (themes), and each theme is structured to have numerous products registered under it.

By introducing Youngwonhee, an internal API performance tracking tool, and analyzing the API query flow, the team discovered a problem where the same query was being called redundantly within a single API call.

This duplicate calling was not simply a code-level mistake, but a problem stemming from the service's structural design itself. To resolve this, performance improvement work was carried out from a structural perspective.