start Command - Medusa CLI Reference

Start the Medusa application in production.

Terminal
❯npx medusa start

Options#

Starting Medusa in Cluster Mode#

Medusa supports starting the Node.js server in cluster mode, which significantly improves performance as the workload and tasks are distributed among all available instances instead of a single one.

Cluster mode is disabled by default. To enable it, pass the --cluster option when starting Medusa:

Terminal
❯npx medusa start --cluster

When the --cluster option is passed without a number or percentage value, Medusa will try to consume all available CPU cores.

Specify Number or Percentage of CPU Cores#

You can specify the number or percentage of CPU cores to be used by passing a number or percentage value to the --cluster option:

Terminal
❯npx medusa start --cluster 2       # Use 2 CPU cores❯npx medusa start --cluster 50%      # Use 50% of available CPU

Specify Number of Servers and Workers#

When running Medusa in cluster mode, you can specify the number or percentage of instances that are servers or workers by passing the --servers and --workers options:

Terminal
❯npx medusa start --cluster 4 --servers 25% --workers 75% # Use 4 CPU cores, with 25% as servers and 75% as workers❯npx medusa start --cluster 4 --servers 1 --workers 3       # Use 4 CPU cores, with 1 as server and 3 as workers❯npx medusa start --cluster 4 --servers 1 --workers 1      # Use 4 CPU cores, with 1 as server and 1 as worker (the remaining 2 will run in shared mode)

When the number or percentage of servers and workers don't add up to the total number of instances in cluster mode, the remaining instances will run in shared mode.