xfy
c6bb75cffe
- Zero-lock atomic EWMA implementation using fixed-point arithmetic - Supports header_time and last_byte_time tracking - Concurrent-safe with CAS retry loop
62 lines
1.4 KiB
Go
62 lines
1.4 KiB
Go
package loadbalance
|
|
|
|
import (
|
|
"sync"
|
|
"testing"
|
|
"time"
|
|
)
|
|
|
|
func TestEWMAStats_BasicRecord(t *testing.T) {
|
|
stats := NewEWMAStats()
|
|
|
|
stats.Record(50*time.Millisecond, 100*time.Millisecond)
|
|
|
|
if stats.HeaderTime() != 50*time.Millisecond {
|
|
t.Errorf("expected header time %v, got %v", 50*time.Millisecond, stats.HeaderTime())
|
|
}
|
|
if stats.LastByteTime() != 100*time.Millisecond {
|
|
t.Errorf("expected last byte time %v, got %v", 100*time.Millisecond, stats.LastByteTime())
|
|
}
|
|
if stats.SampleCount() != 1 {
|
|
t.Errorf("expected sample count 1, got %d", stats.SampleCount())
|
|
}
|
|
}
|
|
|
|
func TestEWMAStats_Convergence(t *testing.T) {
|
|
stats := NewEWMAStats()
|
|
|
|
value := 100 * time.Millisecond
|
|
for i := 0; i < 10; i++ {
|
|
stats.Record(value, value)
|
|
}
|
|
|
|
// alpha=0.3, after 10 samples should be within 10ms of 100ms
|
|
diff := stats.LastByteTime() - value
|
|
if diff < 0 {
|
|
diff = -diff
|
|
}
|
|
if diff > 10*time.Millisecond {
|
|
t.Errorf("expected convergence within 10ms, got diff=%v, value=%v", diff, stats.LastByteTime())
|
|
}
|
|
}
|
|
|
|
func TestEWMAStats_Concurrent(t *testing.T) {
|
|
stats := NewEWMAStats()
|
|
|
|
var wg sync.WaitGroup
|
|
for i := 0; i < 100; i++ {
|
|
wg.Add(1)
|
|
go func() {
|
|
defer wg.Done()
|
|
for j := 0; j < 100; j++ {
|
|
stats.Record(time.Millisecond, 2*time.Millisecond)
|
|
}
|
|
}()
|
|
}
|
|
wg.Wait()
|
|
|
|
if stats.SampleCount() != 100*100 {
|
|
t.Errorf("expected sample count %d, got %d", 100*100, stats.SampleCount())
|
|
}
|
|
}
|