Pointer to the live value for key, or null when absent. Sweeps expired entries before the lookup so a session past its idle TTL is not returned. When refresh is set, a hit stamps the entry as just-active so it survives future idle sweeps.
Pointer to the live value for key, or null when absent. Sweeps expired entries before the lookup so a session past its idle TTL is not returned. When refresh is set, a hit stamps the entry as just-active so it survives future idle sweeps.