go-ethereum/eth/tracers/tracker_test.go
rjl493456442 e50aeac4d0
eth/traces: add state limit (#25812)
This PR introduces a new mechanism in chain tracer for preventing creating too many trace states.

The workflow of chain tracer can be divided into several parts:

- state creator generates trace state in a thread
- state tracer retrieves the trace state and applies the tracing on top in another thread
- state collector gathers all result from state tracer and stream to users

It's basically a producer-consumer model here, while if we imagine that the state producer generates states too fast, then it will lead to accumulate lots of unused states in memory. Even worse, in path-based state scheme it will only keep the latest 128 states in memory, and the newly generated state will invalidate the oldest one by marking it as stale.

The solution for fixing it is to limit the speed of state generation. If there are over 128 states un-consumed in memory, then the creation will be paused until the states are be consumed properly.
2022-10-06 10:48:04 +02:00

172 lines
3.8 KiB
Go

// Copyright 2022 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>
package tracers
import (
"reflect"
"testing"
"time"
)
func TestTracker(t *testing.T) {
var cases = []struct {
limit int
calls []uint64
expHead uint64
}{
// Release in order
{
limit: 3,
calls: []uint64{0, 1, 2},
expHead: 3,
},
{
limit: 3,
calls: []uint64{0, 1, 2, 3, 4, 5},
expHead: 6,
},
// Release out of order
{
limit: 3,
calls: []uint64{1, 2, 0},
expHead: 3,
},
{
limit: 3,
calls: []uint64{1, 2, 0, 5, 4, 3},
expHead: 6,
},
}
for _, c := range cases {
tracker := newStateTracker(c.limit, 0)
for _, call := range c.calls {
tracker.releaseState(call, func() {})
}
tracker.lock.RLock()
head := tracker.oldest
tracker.lock.RUnlock()
if head != c.expHead {
t.Fatalf("Unexpected head want %d got %d", c.expHead, head)
}
}
var calls = []struct {
number uint64
expUsed []bool
expHead uint64
}{
// Release the first one, update the oldest flag
{
number: 0,
expUsed: []bool{false, false, false, false, false},
expHead: 1,
},
// Release the second one, oldest shouldn't be updated
{
number: 2,
expUsed: []bool{false, true, false, false, false},
expHead: 1,
},
// Release the forth one, oldest shouldn't be updated
{
number: 4,
expUsed: []bool{false, true, false, true, false},
expHead: 1,
},
// Release the first one, the first two should all be cleaned,
// and the remaining flags should all be left-shifted.
{
number: 1,
expUsed: []bool{false, true, false, false, false},
expHead: 3,
},
// Release the first one, the first two should all be cleaned
{
number: 3,
expUsed: []bool{false, false, false, false, false},
expHead: 5,
},
}
tracker := newStateTracker(5, 0) // limit = 5, oldest = 0
for _, call := range calls {
tracker.releaseState(call.number, nil)
tracker.lock.RLock()
if !reflect.DeepEqual(tracker.used, call.expUsed) {
t.Fatalf("Unexpected used array")
}
if tracker.oldest != call.expHead {
t.Fatalf("Unexpected head")
}
tracker.lock.RUnlock()
}
}
func TestTrackerWait(t *testing.T) {
var (
tracker = newStateTracker(5, 0) // limit = 5, oldest = 0
result = make(chan error, 1)
doCall = func(number uint64) {
go func() {
result <- tracker.wait(number)
}()
}
checkNoWait = func() {
select {
case <-result:
return
case <-time.NewTimer(time.Second).C:
t.Fatal("No signal fired")
}
}
checkWait = func() {
select {
case <-result:
t.Fatal("Unexpected signal")
case <-time.NewTimer(time.Millisecond * 100).C:
}
}
)
// States [0, 5) should all be available
doCall(0)
checkNoWait()
doCall(4)
checkNoWait()
// State 5 is not available
doCall(5)
checkWait()
// States [1, 6) are available
tracker.releaseState(0, nil)
checkNoWait()
// States [1, 6) are available
doCall(7)
checkWait()
// States [2, 7) are available
tracker.releaseState(1, nil)
checkWait()
// States [3, 8) are available
tracker.releaseState(2, nil)
checkNoWait()
}