Knowing how to scale your app is critical, especially when unexpected load hits. Scaling with Elastic Cloud is easy: simply sign in, visit the configuration page, and drag the memory slider to the desired level. Memory tends to be the limiting factor in Elasticsearch databases. CPU resources and disk IO are scaled up proportionally with memory as your cluster is resized. If you would like to learn more about why memory is so important for Elasticsearch, we’ve got an in-depth on article on Elasticsearch and memory that explains this topic in detail. We also recommend reading Sizing Elasicsearch: Scaling up and out to identify which questions to ask yourself when determining which cluster size is the best fit for your Elasticsearch use case.