+"previous: Upgrading to 2.5.0":#v2_5_0
+
+h3. Default request concurrency, new limit on log requests
+
+The configuration value @API.MaxConcurrentRequests@ (the number of concurrent requests that will be accepted by a single instance of arvados-controller) now has a default value of 64, instead of being unlimited.
+
+New configuration value @API.LogCreateRequestFraction@ (default 0.50) limits requests that post live container logs to the API server, to avoid situations where log messages crowd out other more important requests.
+
+h3. New limit on concurrent workflows
+
+New configuration options @CloudVMs.SupervisorFraction@ (default 0.30) limits the number of concurrent workflow supervisors, to avoid situations where too many workflow runners crowds out actual workers.
+
+h3. Default limit for cloud VM instances
+
+There is a new configuration entry @CloudVMs.MaxInstances@ (default 64) that limits the number of VMs the cloud dispatcher will run at a time. This may need to be adjusted to suit your anticipated workload.
+
+Using the obsolete configuration entry @MaxCloudVMs@, which was previously accepted in config files but not obeyed, will now result in a deprecation warning.
+
+h3. Slow migration on upgrade
+
+This upgrade includes a database schema update (changing an integer column in each table from 32-bit to 64-bit) that may be slow on a large installation. Expect the arvados-api-server package upgrade to take longer than usual.
+
+h2(#v2_5_0). v2.5.0 (2022-12-22)