Abstract: Systems and methods are described for a multi-tenant mode of a serverless code execution system. For instance, a method may include maintaining a set of execution environments, wherein each execution environment is associated with a serverless function, wherein the serverless function is associated with a software as a service (SaaS) provider that is a tenant of a cloud services provider, wherein the SaaS provider provides services to sub-tenants, wherein the set of execution environments are partitioned based on sub-tenants of the SaaS provider; receiving a call to execute a serverless function, wherein the call includes a serverless function identifier and a sub-tenant identifier; identifying a sub-tenant-specific execution environment of the set of execution environments that is associated with the sub-tenant; and in response to identifying the tenant-specific execution environment, invoking the serverless function on the sub-tenant-specific execution environment.

Abstract: Systems and methods are described for reducing cold starts code within a serverless code execution system by providing a set of environments reserved for the code. A frontend distribute calls for execution among a set of manager devices that manage environments in the system, distributed in a manner that groups calls together and attempts to distribute calls of the same group to a stable subset of the manager devices. In the case that a user reduces or eliminates the number of environments reserved for the code, a frontend continues to distribute calls for execution of the code to those environments while they continue to be used. This reduces cold starts that might otherwise occur during reduction or elimination of reserved environments.

Abstract: Systems and methods are described for reducing cold starts code within a serverless code execution system by providing a set of environments reserved for the code. A frontend distribute calls for execution among a set of manager devices that manage environments in the system, distributed in a manner that groups calls together and attempts to distribute calls of the same group to a stable subset of the manager devices. In the case that a user reduces or eliminates the number of environments reserved for the code, a frontend continues to distribute calls for execution of the code to those environments while they continue to be used. This reduces cold starts that might otherwise occur during reduction or elimination of reserved environments.

Abstract: Systems and methods are described for reducing cold starts code within a serverless code execution system by providing a set of environments reserved for the code. A frontend utilizes a consistent hash ring to distribute calls for execution among a set of manager devices that manage environments in the system, distributed in a manner that groups calls together and attempts to distribute calls of the same group to a stable subset of the manager devices. Each group is assigned an arc, representing a subset of manager devices. When a call is received to execute a set of code that has environments reserved, the frontend distributes the call to a manager device of a reserved arc. When a call is received to execute a set of code that does not have environment reserved, the frontend distributes the call to an arc associated with an arc for unreserved executions.