Scaling
Handle a traffic spike: more replicas for a service, more machines for the cluster, and what it costs.
Two levels
Section titled “Two levels”- The service: more replicas of your application, on the existing machines.
- The cluster: more machines, to make room for the replicas.
The two work together: when the replicas no longer fit on the machines, AutoPilot adds more.
More replicas for a service
Section titled “More replicas for a service”In the application’s panel, Resources tab, Number of replicas:
- Fixed: the number of Replicas you choose;
- Automatic: Fransys adds or removes replicas depending on load.
Each replica reserves the CPU and memory set in Reservations. These reservations are what fill up the machines.
More machines for the cluster
Section titled “More machines for the cluster”- AutoPilot, within a budget: Fransys picks the machines and adds more as load grows, up to your cap.
- AutoPilot, with my machines: it stays between each group’s minimum and maximum.
- Choose myself: the number of machines doesn’t move; change it in Change the configuration.
See AutoPilot and cap.
What it costs
Section titled “What it costs”An added machine is billed for as long as it runs, by the hour. With AutoPilot within a budget, the total never goes over the cap: once it’s reached, no machine is added, and you’re told by email.
The cluster page shows the Free capacity, paid for but unused, and usage project by project. If it stays high for a long time, reduce the machines or the reservations.
Before an expected spike
Section titled “Before an expected spike”A launch, a campaign: switch to a few replicas in fixed mode, and check that the cap leaves some headroom. Your agent can prepare it in a plan: “Get the shop project ready for a traffic spike tomorrow, without going over €300 a month.”