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Use timevals

This commit is contained in:
Patrick Mylund Nielsen 2015-11-30 14:47:22 -05:00
parent 1924ec3baf
commit 01842a547c
2 changed files with 34 additions and 15 deletions

View File

@ -7,22 +7,23 @@ import (
"os"
"runtime"
"sync"
"syscall"
"time"
)
var emptyTime = time.Time{}
type Item struct {
Object interface{}
Expiration int64
Expiration syscall.Timeval
}
// Returns true if the item has expired.
func (item Item) Expired() bool {
if item.Expiration == 0 {
if item.Expiration.Sec == 0 {
return false
}
return time.Now().UnixNano() > item.Expiration
var tv syscall.Timeval
syscall.Gettimeofday(&tv)
return tv.Sec > item.Expiration.Sec || (tv.Sec == item.Expiration.Sec && tv.Usec > item.Expiration.Usec)
}
const (
@ -59,12 +60,12 @@ func (c *cache) Set(k string, x interface{}, d time.Duration) {
}
func (c *cache) set(k string, x interface{}, d time.Duration) {
var e int64
var e syscall.Timeval
if d == DefaultExpiration {
d = c.defaultExpiration
}
if d > 0 {
e = time.Now().Add(d).UnixNano()
e = syscall.NsecToTimeval(time.Now().Add(d).UnixNano())
}
c.items[k] = Item{
Object: x,
@ -106,20 +107,36 @@ func (c *cache) Get(k string) (interface{}, bool) {
c.mu.RLock()
// "Inlining" of get and expired
item, found := c.items[k]
if !found || (item.Expiration > 0 && time.Now().UnixNano() > item.Expiration) {
if !found {
c.mu.RUnlock()
return nil, false
}
if item.Expiration.Sec > 0 {
var tv syscall.Timeval
syscall.Gettimeofday(&tv)
if tv.Sec > item.Expiration.Sec || (tv.Sec == item.Expiration.Sec && tv.Usec > item.Expiration.Usec) {
c.mu.RUnlock()
return nil, false
}
}
c.mu.RUnlock()
return item.Object, found
return item.Object, true
}
func (c *cache) get(k string) (interface{}, bool) {
item, found := c.items[k]
// "Inlining" of expired
if !found || (item.Expiration > 0 && time.Now().UnixNano() > item.Expiration) {
if !found {
return nil, false
}
// "Inlining" of Expired
if item.Expiration.Sec > 0 {
var tv syscall.Timeval
syscall.Gettimeofday(&tv)
if tv.Sec > item.Expiration.Sec || (tv.Sec == item.Expiration.Sec && tv.Usec > item.Expiration.Usec) {
c.mu.RUnlock()
return nil, false
}
}
return item.Object, true
}
@ -874,11 +891,12 @@ type keyAndValue struct {
// Delete all expired items from the cache.
func (c *cache) DeleteExpired() {
var evictedItems []keyAndValue
now := time.Now().UnixNano()
var now syscall.Timeval
syscall.Gettimeofday(&now)
c.mu.Lock()
for k, v := range c.items {
// "Inlining" of expired
if v.Expiration > 0 && now > v.Expiration {
if v.Expiration.Sec > 0 && (now.Sec > v.Expiration.Sec || (now.Sec == v.Expiration.Sec && now.Usec > v.Expiration.Usec)) {
ov, evicted := c.delete(k)
if evicted {
evictedItems = append(evictedItems, keyAndValue{k, ov})

View File

@ -6,6 +6,7 @@ import (
"runtime"
"strconv"
"sync"
"syscall"
"testing"
"time"
)
@ -110,11 +111,11 @@ func TestNewFrom(t *testing.T) {
m := map[string]Item{
"a": Item{
Object: 1,
Expiration: 0,
Expiration: syscall.Timeval{},
},
"b": Item{
Object: 2,
Expiration: 0,
Expiration: syscall.Timeval{},
},
}
tc := NewFrom(DefaultExpiration, 0, m)