Struct PoolConfig 

pub struct PoolConfig {
    pub max_idle: usize,
    pub idle_timeout: Duration,
}

How many idle connections to keep, and how long to keep them.

Defaults are deliberately conservative. An idle pooled connection holds one of the engine’s connection permits (num_workers * 200, of which the main listener gets 35%), so a large pool across many client processes can starve the server while mostly idle. Raise these only after measuring with the queue-depths command under production-like load.

Fields

max_idle: usize

Maximum idle connections retained. Never unbounded.

idle_timeout: Duration

Discard an idle connection older than this.

Must stay shorter than any server or firewall idle reaper so the client drops a connection before the peer does — that is what keeps the stale-connection retry path rare rather than routine.

Trait Implementations

impl Clone for PoolConfig

fn clone(&self) -> PoolConfig

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for PoolConfig

impl Debug for PoolConfig

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for PoolConfig

fn default() -> Self

Returns the “default value” for a type.