Marek Siarkowicz 2fc1485f29 tests: Make linearizability traffic extendable
Signed-off-by: Marek Siarkowicz <siarkowicz@google.com>
2022-11-14 23:14:10 +01:00

108 lines
2.6 KiB
Go

// Copyright 2022 The etcd Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package linearizability
import (
"context"
"fmt"
"math/rand"
"time"
"golang.org/x/time/rate"
)
var (
DefaultTraffic Traffic = readWriteSingleKey{key: "key", writes: []opChance{{operation: Put, chance: 100}}}
)
type Traffic interface {
Run(ctx context.Context, c *recordingClient, limiter *rate.Limiter)
}
type readWriteSingleKey struct {
key string
writes []opChance
}
type opChance struct {
operation Operation
chance int
}
func (t readWriteSingleKey) Run(ctx context.Context, c *recordingClient, limiter *rate.Limiter) {
maxOperationsPerClient := 1000000
minId := maxOperationsPerClient * c.id
maxId := maxOperationsPerClient * (c.id + 1)
for writeId := minId; writeId < maxId; {
select {
case <-ctx.Done():
return
default:
}
// Execute one read per one write to avoid operation history include too many failed writes when etcd is down.
err := t.Read(ctx, c, limiter)
if err != nil {
continue
}
// Provide each write with unique id to make it easier to validate operation history.
t.Write(ctx, c, limiter, writeId)
writeId++
}
return
}
func (t readWriteSingleKey) Read(ctx context.Context, c *recordingClient, limiter *rate.Limiter) error {
getCtx, cancel := context.WithTimeout(ctx, 20*time.Millisecond)
err := c.Get(getCtx, t.key)
cancel()
if err == nil {
limiter.Wait(ctx)
}
return err
}
func (t readWriteSingleKey) Write(ctx context.Context, c *recordingClient, limiter *rate.Limiter, id int) error {
putCtx, cancel := context.WithTimeout(ctx, 20*time.Millisecond)
var err error
switch t.pickWriteOperation() {
case Put:
err = c.Put(putCtx, t.key, fmt.Sprintf("%d", id))
default:
panic("invalid operation")
}
cancel()
if err == nil {
limiter.Wait(ctx)
}
return err
}
func (t readWriteSingleKey) pickWriteOperation() Operation {
sum := 0
for _, op := range t.writes {
sum += op.chance
}
roll := rand.Int() % sum
for _, op := range t.writes {
if roll < op.chance {
return op.operation
}
roll -= op.chance
}
panic("unexpected")
}