Expand description
A thread-safe indexed object pool with automatic return and attach/detach semantics.
The goal of an object pool is to reuse expensive to allocate objects or frequently allocated objects. This pool implementation allows to index different object pools of the same type as subpools. For example you could use this to pool SSH connection objects, indexed by ipaddress:port.
This pool is bound to sizes to avoid to keep allocations in control. There are 2 different
sizes that can be setup at creation time, max_pool_indexes
and max_single_pool_size
, the
former controlling how many indexes the pool can contain and the latter controlling the max
size of the subpool of a single index.
On top of that indexes have an expiration time expressed as a duration.
§Examples
§Creating a Pool
The default pool creation looks like this, with 32 indexes with a capacity of 8 elements expiring after 5 minutes from creation :
use indexed_pool::Pool;
let pool: Pool<String> = Pool::default();
Example pool with 64 Vec<u8>
with capacity of 64 elements each expiring after 10 seconds:
use std::time::Duration;
use indexed_pool::Pool;
let pool: Pool<u8> = Pool::new(64, 64, Duration::from_secs(10));
§Using a Pool
Basic usage for pulling from the pool
use indexed_pool::Pool;
struct Obj {
size: usize,
}
let pool: Pool<Obj> = Pool::default();
let obj = pool.pull("item1", || Obj{size: 1});
assert_eq!(obj.size, 1);
let obj2 = pool.pull("item1", || Obj{size: 1});
assert_eq!(obj.size, 1);
Pull from pool and detach()
use indexed_pool::Pool;
struct Obj {
size: usize,
}
let pool: Pool<Obj> = Pool::default();
let obj = pool.pull("item1", || Obj{size: 1});
assert_eq!(obj.size, 1);
let obj2 = pool.pull("item1", || Obj{size: 1});
assert_eq!(obj.size, 1);
let (pool, obj) = obj.detach();
assert_eq!(obj.size, 1);
pool.attach("item1", obj);
§Using Across Threads
You simply wrap the pool in a std::sync::Arc
use std::sync::Arc;
use indexed_pool::Pool;
let pool: Arc<Pool<String>> = Arc::new(Pool::default());
§Warning
Objects in the pool are not automatically reset, they are returned but NOT reset
You may want to call object.reset()
or object.clear()
or any other equivalent for the object that you are using, after pulling from the pool