OpenSSL session cache concurrency behavior with session IDs and tickets

OpenSSL provides TLS session resumption via server-side session cache and via Session Tickets per RFC 5077. The documented capability aims to reduce handshake latency for returning clients by reusing session state. Under concurrent connection loads, the behavior of the session cache becomes relevant for performance design.

Server-side caching stores session state in memory for rapid lookup, while session tickets move state to the client and remove server lookups. The documented limits for cache size, locking, and eviction under high concurrency are not clearly specified, and implementation-specific variance is noted for eviction policies.

What limits are documented for the default in-memory session cache under concurrent TLS handshakes? Is session cache locking documented as affecting handshake latency under concurrent requests? Is the eviction policy for session IDs configurable and documented compared with session tickets?