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|
package sctp
import (
"math"
"sync/atomic"
"testing"
"time"
"github.com/stretchr/testify/assert"
)
func TestRTOManager(t *testing.T) {
t.Run("initial values", func(t *testing.T) {
m := newRTOManager()
assert.Equal(t, rtoInitial, m.rto, "should be rtoInitial")
assert.Equal(t, rtoInitial, m.getRTO(), "should be rtoInitial")
assert.Equal(t, float64(0), m.srtt, "should be 0")
assert.Equal(t, float64(0), m.rttvar, "should be 0")
})
t.Run("RTO calculation (small RTT)", func(t *testing.T) {
var rto float64
m := newRTOManager()
exp := []int32{
1800,
1500,
1275,
1106,
1000, // capped at RTO.Min
}
for i := 0; i < 5; i++ {
m.setNewRTT(600)
rto = m.getRTO()
assert.Equal(t, exp[i], int32(math.Floor(rto)), "should be equal")
}
})
t.Run("RTO calculation (large RTT)", func(t *testing.T) {
var rto float64
m := newRTOManager()
exp := []int32{
60000, // capped at RTO.Max
60000, // capped at RTO.Max
60000, // capped at RTO.Max
55312,
48984,
}
for i := 0; i < 5; i++ {
m.setNewRTT(30000)
rto = m.getRTO()
assert.Equal(t, exp[i], int32(math.Floor(rto)), "should be equal")
}
})
t.Run("calculateNextTimeout", func(t *testing.T) {
var rto float64
rto = calculateNextTimeout(1.0, 0)
assert.Equal(t, float64(1), rto, "should match")
rto = calculateNextTimeout(1.0, 1)
assert.Equal(t, float64(2), rto, "should match")
rto = calculateNextTimeout(1.0, 2)
assert.Equal(t, float64(4), rto, "should match")
rto = calculateNextTimeout(1.0, 30)
assert.Equal(t, float64(60000), rto, "should match")
rto = calculateNextTimeout(1.0, 63)
assert.Equal(t, float64(60000), rto, "should match")
rto = calculateNextTimeout(1.0, 64)
assert.Equal(t, float64(60000), rto, "should match")
})
t.Run("reset", func(t *testing.T) {
m := newRTOManager()
for i := 0; i < 10; i++ {
m.setNewRTT(200)
}
m.reset()
assert.Equal(t, rtoInitial, m.getRTO(), "should be rtoInitial")
assert.Equal(t, float64(0), m.srtt, "should be 0")
assert.Equal(t, float64(0), m.rttvar, "should be 0")
})
}
type (
onRTO func(id int, n uint)
onRtxFailure func(id int)
)
type testTimerObserver struct {
onRTO onRTO
onRtxFailure onRtxFailure
}
func (o *testTimerObserver) onRetransmissionTimeout(id int, n uint) {
o.onRTO(id, n)
}
func (o *testTimerObserver) onRetransmissionFailure(id int) {
o.onRtxFailure(id)
}
func TestRtxTimer(t *testing.T) {
t.Run("callback interval", func(t *testing.T) {
timerID := 0
var nCbs int32
rt := newRTXTimer(timerID, &testTimerObserver{
onRTO: func(id int, nRtos uint) {
atomic.AddInt32(&nCbs, 1)
// 30 : 1 (30)
// 60 : 2 (90)
// 120: 3 (210)
// 240: 4 (550) <== expected in 650 msec
assert.Equal(t, timerID, id, "unexpted timer ID: %d", id)
},
onRtxFailure: func(id int) {},
}, pathMaxRetrans)
assert.False(t, rt.isRunning(), "should not be running")
// since := time.Now()
ok := rt.start(30)
assert.True(t, ok, "should be true")
assert.True(t, rt.isRunning(), "should be running")
time.Sleep(650 * time.Millisecond)
rt.stop()
assert.False(t, rt.isRunning(), "should not be running")
assert.Equal(t, int32(4), atomic.LoadInt32(&nCbs), "should be called 4 times")
})
t.Run("last start wins", func(t *testing.T) {
timerID := 3
var nCbs int32
rt := newRTXTimer(timerID, &testTimerObserver{
onRTO: func(id int, nRtos uint) {
atomic.AddInt32(&nCbs, 1)
assert.Equal(t, timerID, id, "unexpted timer ID: %d", id)
},
onRtxFailure: func(id int) {},
}, pathMaxRetrans)
interval := float64(30.0)
ok := rt.start(interval)
assert.True(t, ok, "should be accepted")
ok = rt.start(interval * 99) // should ignored
assert.False(t, ok, "should be ignored")
ok = rt.start(interval * 99) // should ignored
assert.False(t, ok, "should be ignored")
time.Sleep(time.Duration(interval*1.5) * time.Millisecond)
rt.stop()
assert.False(t, rt.isRunning(), "should not be running")
assert.Equal(t, int32(1), atomic.LoadInt32(&nCbs), "must be called once")
})
t.Run("stop right afeter start", func(t *testing.T) {
timerID := 3
var nCbs int32
rt := newRTXTimer(timerID, &testTimerObserver{
onRTO: func(id int, nRtos uint) {
atomic.AddInt32(&nCbs, 1)
assert.Equal(t, timerID, id, "unexpted timer ID: %d", id)
},
onRtxFailure: func(id int) {},
}, pathMaxRetrans)
interval := float64(30.0)
ok := rt.start(interval)
assert.True(t, ok, "should be accepted")
rt.stop()
time.Sleep(time.Duration(interval*1.5) * time.Millisecond)
rt.stop()
assert.False(t, rt.isRunning(), "should not be running")
assert.Equal(t, int32(0), atomic.LoadInt32(&nCbs), "no callback should be made")
})
t.Run("start, stop then start", func(t *testing.T) {
timerID := 1
var nCbs int32
rt := newRTXTimer(timerID, &testTimerObserver{
onRTO: func(id int, nRtos uint) {
atomic.AddInt32(&nCbs, 1)
assert.Equal(t, timerID, id, "unexpted timer ID: %d", id)
},
onRtxFailure: func(id int) {},
}, pathMaxRetrans)
interval := float64(30.0)
ok := rt.start(interval)
assert.True(t, ok, "should be accepted")
rt.stop()
assert.False(t, rt.isRunning(), "should NOT be running")
ok = rt.start(interval)
assert.True(t, ok, "should be accepted")
assert.True(t, rt.isRunning(), "should be running")
time.Sleep(time.Duration(interval*1.5) * time.Millisecond)
rt.stop()
assert.False(t, rt.isRunning(), "should NOT be running")
assert.Equal(t, int32(1), atomic.LoadInt32(&nCbs), "must be called once")
})
t.Run("start and stop in a tight loop", func(t *testing.T) {
timerID := 2
var nCbs int32
rt := newRTXTimer(timerID, &testTimerObserver{
onRTO: func(id int, nRtos uint) {
atomic.AddInt32(&nCbs, 1)
t.Log("onRTO() called")
assert.Equal(t, timerID, id, "unexpted timer ID: %d", id)
},
onRtxFailure: func(id int) {},
}, pathMaxRetrans)
for i := 0; i < 1000; i++ {
ok := rt.start(30)
assert.True(t, ok, "should be accepted")
assert.True(t, rt.isRunning(), "should be running")
rt.stop()
assert.False(t, rt.isRunning(), "should NOT be running")
}
assert.Equal(t, int32(0), atomic.LoadInt32(&nCbs), "no callback should be made")
})
t.Run("timer should stop after rtx failure", func(t *testing.T) {
timerID := 4
var nCbs int32
doneCh := make(chan bool)
since := time.Now()
var elapsed float64 // in seconds
rt := newRTXTimer(timerID, &testTimerObserver{
onRTO: func(id int, nRtos uint) {
assert.Equal(t, timerID, id, "unexpted timer ID: %d", id)
t.Logf("onRTO: n=%d elapsed=%.03f\n", nRtos, time.Since(since).Seconds())
atomic.AddInt32(&nCbs, 1)
},
onRtxFailure: func(id int) {
assert.Equal(t, timerID, id, "unexpted timer ID: %d", id)
elapsed = time.Since(since).Seconds()
t.Logf("onRtxFailure: elapsed=%.03f\n", elapsed)
doneCh <- true
},
}, pathMaxRetrans)
// RTO(msec) Total(msec)
// 10 10 1st RTO
// 20 30 2nd RTO
// 40 70 3rd RTO
// 80 150 4th RTO
// 160 310 5th RTO (== Path.Max.Retrans)
// 320 630 Failure
interval := float64(10.0)
ok := rt.start(interval)
assert.True(t, ok, "should be accepted")
assert.True(t, rt.isRunning(), "should be running")
<-doneCh
assert.False(t, rt.isRunning(), "should not be running")
assert.Equal(t, int32(5), atomic.LoadInt32(&nCbs), "should be called 5 times")
assert.True(t, elapsed > 0.600, "must have taken more than 600 msec")
assert.True(t, elapsed < 0.700, "must fail in less than 700 msec")
})
t.Run("timer should not stop if maxRetrans is 0", func(t *testing.T) {
timerID := 4
maxRtos := uint(6)
var nCbs int32
doneCh := make(chan bool)
since := time.Now()
var elapsed float64 // in seconds
rt := newRTXTimer(timerID, &testTimerObserver{
onRTO: func(id int, nRtos uint) {
assert.Equal(t, timerID, id, "unexpted timer ID: %d", id)
elapsed = time.Since(since).Seconds()
t.Logf("onRTO: n=%d elapsed=%.03f\n", nRtos, elapsed)
atomic.AddInt32(&nCbs, 1)
if nRtos == maxRtos {
doneCh <- true
}
},
onRtxFailure: func(id int) {
assert.Fail(t, "timer should not fail")
},
}, 0)
// RTO(msec) Total(msec)
// 10 10 1st RTO
// 20 30 2nd RTO
// 40 70 3rd RTO
// 80 150 4th RTO
// 160 310 5th RTO
// 320 630 6th RTO => exit test (timer should still be running)
interval := float64(10.0)
ok := rt.start(interval)
assert.True(t, ok, "should be accepted")
assert.True(t, rt.isRunning(), "should be running")
<-doneCh
assert.True(t, rt.isRunning(), "should still be running")
assert.Equal(t, int32(6), atomic.LoadInt32(&nCbs), "should be called 6 times")
assert.True(t, elapsed > 0.600, "must have taken more than 600 msec")
assert.True(t, elapsed < 0.700, "must fail in less than 700 msec")
rt.stop()
})
t.Run("stop timer that is not running is noop", func(t *testing.T) {
timerID := 5
doneCh := make(chan bool)
rt := newRTXTimer(timerID, &testTimerObserver{
onRTO: func(id int, nRtos uint) {
assert.Equal(t, timerID, id, "unexpted timer ID: %d", id)
doneCh <- true
},
onRtxFailure: func(id int) {},
}, pathMaxRetrans)
for i := 0; i < 10; i++ {
rt.stop()
}
ok := rt.start(20)
assert.True(t, ok, "should be accepted")
assert.True(t, rt.isRunning(), "must be running")
<-doneCh
rt.stop()
assert.False(t, rt.isRunning(), "must be false")
})
t.Run("closed timer won't start", func(t *testing.T) {
var rtoCount int
timerID := 6
rt := newRTXTimer(timerID, &testTimerObserver{
onRTO: func(id int, nRtos uint) {
rtoCount++
},
onRtxFailure: func(id int) {},
}, pathMaxRetrans)
ok := rt.start(20)
assert.True(t, ok, "should be accepted")
assert.True(t, rt.isRunning(), "must be running")
rt.close()
assert.False(t, rt.isRunning(), "must be false")
ok = rt.start(20)
assert.False(t, ok, "should not start")
assert.False(t, rt.isRunning(), "must not be running")
time.Sleep(100 * time.Millisecond)
assert.Equal(t, 0, rtoCount, "RTO should not occur")
})
}
|
