README
¶
TTL
Generic concurency safe Time-To-Live list.
func ExampleTTL() {
list := ttl.New[int](
func(key int) {
fmt.Printf("timed out: %v\n", key)
},
)
list.Put(42, 1*time.Millisecond)
<-list.Wait() // optionally wait for everything to time out.
list.Stop() // stops the internal worker.
// Output:
// timed out: 42
}
Uses channels for internals sync, operations are not time compensated. Timeout events are always a few microseconds late.
It stores keys in a slice sorted by key timeout in ascending order and continually resets a ticker that runs in a worker routine to a timeout of the next key in queue.
Has room for optimizations. Adding items whose timeout is always greater than the last in the list is fast but is slow if timeouts being added continually decrease, i.e. are put to the front of the key list.
goos: linux
goarch: amd64
pkg: github.com/vedranvuk/ttl
cpu: 11th Gen Intel(R) Core(TM) i7-1165G7 @ 2.80GHz
BenchmarkPutAscending
BenchmarkPutAscending-8 732739 1643 ns/op
BenchmarkPutDescending
BenchmarkPutDescending-8 40346 182233 ns/op
BenchmarkPutRandom
BenchmarkPutRandom-8 63727 146609 ns/op
PASS
ok github.com/vedranvuk/ttl 20.472s
License
MIT
Documentation
¶
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
var ErrNotFound = errors.New("not found")
ErrNotFound is returned when delete does not find the item to be deleted.
var ErrNotRunning = errors.New("ttl is not running")
ErrNotRunning is returned when a timeout is being added or deleted to/from a ttl that has been stopped.
Functions ¶
This section is empty.
Types ¶
type TTL ¶
type TTL[K comparable] struct { // contains filtered or unexported fields }
TTL is a Time-To-Live list of comparrable keys that exist only for the duration specified. When a key expires TTL fires the callback specified in New.
TTL worker should be stopped manually after use with TTL.Stop.
It works by maintaining an ascending sorted queue of key timeout times that get on the next tick that is upated each time a timeout, update, put or delete occur updates a ticker that ticks at the next timeout time in the queue and fires timeout callback. Precision is "okay", error is always a delay.
Example ¶
package main
import (
"fmt"
"time"
"github.com/vedranvuk/ttl"
)
func main() {
list := ttl.New[int](
func(key int) {
fmt.Printf("timed out: %v\n", key)
},
)
list.Put(42, 1*time.Millisecond)
<-list.Wait()
list.Stop()
}
Output: timed out: 42
func New ¶
func New[K comparable](cb func(key K)) *TTL[K]
Returns a new TTL which calls the optional cb each time a key expires.
func (*TTL[K]) Delete ¶
Delete removes a key from the list. Returns ErrNotRunning if ttl is stopped.
func (*TTL[K]) Put ¶
Put adds the key to ttl which will last for duration. If key is already present its timeout is reset to duration. Returns ErrNotRunning if ttl is stopped.
Source Files