diode: let use a waiter instead of a poller by using 0 as a poolInterval

This commit is contained in:
Olivier Poitrey 2018-10-31 16:57:15 -07:00
parent baa31cfa85
commit e7627a4f73
3 changed files with 42 additions and 23 deletions

View File

@ -19,12 +19,16 @@ var bufPool = &sync.Pool{
type Alerter func(missed int) type Alerter func(missed int)
type diodeFetcher interface {
diodes.Diode
Next() diodes.GenericDataType
}
// Writer is a io.Writer wrapper that uses a diode to make Write lock-free, // Writer is a io.Writer wrapper that uses a diode to make Write lock-free,
// non-blocking and thread safe. // non-blocking and thread safe.
type Writer struct { type Writer struct {
w io.Writer w io.Writer
d *diodes.ManyToOne d diodeFetcher
p *diodes.Poller
c context.CancelFunc c context.CancelFunc
done chan struct{} done chan struct{}
} }
@ -35,25 +39,34 @@ type Writer struct {
// //
// Use a diode.Writer when // Use a diode.Writer when
// //
// wr := diode.NewWriter(w, 1000, 10 * time.Millisecond, func(missed int) { // wr := diode.NewWriter(w, 1000, 0, func(missed int) {
// log.Printf("Dropped %d messages", missed) // log.Printf("Dropped %d messages", missed)
// }) // })
// log := zerolog.New(wr) // log := zerolog.New(wr)
// //
// If poolInterval is greater than 0, a poller is used otherwise a waiter is
// used.
// //
// See code.cloudfoundry.org/go-diodes for more info on diode. // See code.cloudfoundry.org/go-diodes for more info on diode.
func NewWriter(w io.Writer, size int, poolInterval time.Duration, f Alerter) Writer { func NewWriter(w io.Writer, size int, poolInterval time.Duration, f Alerter) Writer {
ctx, cancel := context.WithCancel(context.Background()) ctx, cancel := context.WithCancel(context.Background())
d := diodes.NewManyToOne(size, diodes.AlertFunc(f))
dw := Writer{ dw := Writer{
w: w, w: w,
d: d,
p: diodes.NewPoller(d,
diodes.WithPollingInterval(poolInterval),
diodes.WithPollingContext(ctx)),
c: cancel, c: cancel,
done: make(chan struct{}), done: make(chan struct{}),
} }
if f == nil {
f = func(int) {}
}
d := diodes.NewManyToOne(size, diodes.AlertFunc(f))
if poolInterval > 0 {
dw.d = diodes.NewPoller(d,
diodes.WithPollingInterval(poolInterval),
diodes.WithPollingContext(ctx))
} else {
dw.d = diodes.NewWaiter(d,
diodes.WithWaiterContext(ctx))
}
go dw.poll() go dw.poll()
return dw return dw
} }
@ -80,7 +93,7 @@ func (dw Writer) Close() error {
func (dw Writer) poll() { func (dw Writer) poll() {
defer close(dw.done) defer close(dw.done)
for { for {
d := dw.p.Next() d := dw.d.Next()
if d == nil { if d == nil {
return return
} }

View File

@ -5,14 +5,13 @@ package diode_test
import ( import (
"fmt" "fmt"
"os" "os"
"time"
"github.com/rs/zerolog" "github.com/rs/zerolog"
"github.com/rs/zerolog/diode" "github.com/rs/zerolog/diode"
) )
func ExampleNewWriter() { func ExampleNewWriter() {
w := diode.NewWriter(os.Stdout, 1000, 10*time.Millisecond, func(missed int) { w := diode.NewWriter(os.Stdout, 1000, 0, func(missed int) {
fmt.Printf("Dropped %d messages\n", missed) fmt.Printf("Dropped %d messages\n", missed)
}) })
log := zerolog.New(w) log := zerolog.New(w)

View File

@ -16,7 +16,7 @@ import (
func TestNewWriter(t *testing.T) { func TestNewWriter(t *testing.T) {
buf := bytes.Buffer{} buf := bytes.Buffer{}
w := diode.NewWriter(&buf, 1000, 10*time.Millisecond, func(missed int) { w := diode.NewWriter(&buf, 1000, 0, func(missed int) {
fmt.Printf("Dropped %d messages\n", missed) fmt.Printf("Dropped %d messages\n", missed)
}) })
log := zerolog.New(w) log := zerolog.New(w)
@ -33,7 +33,13 @@ func TestNewWriter(t *testing.T) {
func Benchmark(b *testing.B) { func Benchmark(b *testing.B) {
log.SetOutput(ioutil.Discard) log.SetOutput(ioutil.Discard)
defer log.SetOutput(os.Stderr) defer log.SetOutput(os.Stderr)
w := diode.NewWriter(ioutil.Discard, 100000, 10*time.Millisecond, nil) benchs := map[string]time.Duration{
"Waiter": 0,
"Pooler": 10 * time.Millisecond,
}
for name, interval := range benchs {
b.Run(name, func(b *testing.B) {
w := diode.NewWriter(ioutil.Discard, 100000, interval, nil)
log := zerolog.New(w) log := zerolog.New(w)
defer w.Close() defer w.Close()
@ -43,5 +49,6 @@ func Benchmark(b *testing.B) {
log.Print("test") log.Print("test")
} }
}) })
})
}
} }