go-pulse/log/logger_test.go
Martin Holst Swende dd0d0a2522
slog: faster and less memory-consumption (#28621)
These changes improves the performance of the non-coloured terminal formatting, _quite a lot_. 

```
name               old time/op    new time/op    delta
TerminalHandler-8    10.2µs ±15%     5.4µs ± 9%  -47.02%  (p=0.008 n=5+5)

name               old alloc/op   new alloc/op   delta
TerminalHandler-8    2.17kB ± 0%    0.40kB ± 0%  -81.46%  (p=0.008 n=5+5)

name               old allocs/op  new allocs/op  delta
TerminalHandler-8      33.0 ± 0%       5.0 ± 0%  -84.85%  (p=0.008 n=5+5)
```

I tried to _somewhat_ organize the commits, but the it might still be a bit chaotic. Some core insights: 

- The function `terminalHandler.Handl` uses a mutex, and writes all output immediately to 'upstream'. Thus, it can reuse a scratch-buffer every time. 
- This buffer can be propagated internally, making all the internal formatters either write directly to it,
- OR, make  use of the `tmp := buf.AvailableBuffer()` in some cases, where a byte buffer "extra capacity" can be temporarily used. 
- The `slog` package  uses `Attr` by value. It makes sense to minimize operating on them, since iterating / collecting into a new slice, iterating again etc causes copy-on-heap. Better to operate on them only once. 
- If we want to do padding, it's better to copy from a constant `space`-buffer than to invoke `bytes.Repeat` every single time.
2023-12-01 13:28:20 +01:00

175 lines
4.7 KiB
Go

package log
import (
"bytes"
"fmt"
"io"
"math/big"
"os"
"strings"
"testing"
"time"
"github.com/holiman/uint256"
"golang.org/x/exp/slog"
)
// TestLoggingWithVmodule checks that vmodule works.
func TestLoggingWithVmodule(t *testing.T) {
out := new(bytes.Buffer)
glog := NewGlogHandler(NewTerminalHandlerWithLevel(out, LevelTrace, false))
glog.Verbosity(LevelCrit)
logger := NewLogger(glog)
logger.Warn("This should not be seen", "ignored", "true")
glog.Vmodule("logger_test.go=5")
logger.Trace("a message", "foo", "bar")
have := out.String()
// The timestamp is locale-dependent, so we want to trim that off
// "INFO [01-01|00:00:00.000] a messag ..." -> "a messag..."
have = strings.Split(have, "]")[1]
want := " a message foo=bar\n"
if have != want {
t.Errorf("\nhave: %q\nwant: %q\n", have, want)
}
}
func TestTerminalHandlerWithAttrs(t *testing.T) {
out := new(bytes.Buffer)
glog := NewGlogHandler(NewTerminalHandlerWithLevel(out, LevelTrace, false).WithAttrs([]slog.Attr{slog.String("baz", "bat")}))
glog.Verbosity(LevelTrace)
logger := NewLogger(glog)
logger.Trace("a message", "foo", "bar")
have := out.String()
// The timestamp is locale-dependent, so we want to trim that off
// "INFO [01-01|00:00:00.000] a messag ..." -> "a messag..."
have = strings.Split(have, "]")[1]
want := " a message baz=bat foo=bar\n"
if have != want {
t.Errorf("\nhave: %q\nwant: %q\n", have, want)
}
}
func BenchmarkTraceLogging(b *testing.B) {
SetDefault(NewLogger(NewTerminalHandler(os.Stderr, true)))
b.ResetTimer()
for i := 0; i < b.N; i++ {
Trace("a message", "v", i)
}
}
func BenchmarkTerminalHandler(b *testing.B) {
l := NewLogger(NewTerminalHandler(io.Discard, false))
benchmarkLogger(b, l)
}
func BenchmarkLogfmtHandler(b *testing.B) {
l := NewLogger(LogfmtHandler(io.Discard))
benchmarkLogger(b, l)
}
func BenchmarkJSONHandler(b *testing.B) {
l := NewLogger(JSONHandler(io.Discard))
benchmarkLogger(b, l)
}
func benchmarkLogger(b *testing.B, l Logger) {
var (
bb = make([]byte, 10)
tt = time.Now()
bigint = big.NewInt(100)
nilbig *big.Int
err = fmt.Errorf("Oh nooes it's crap")
)
b.ReportAllocs()
b.ResetTimer()
for i := 0; i < b.N; i++ {
l.Info("This is a message",
"foo", int16(i),
"bytes", bb,
"bonk", "a string with text",
"time", tt,
"bigint", bigint,
"nilbig", nilbig,
"err", err)
}
b.StopTimer()
}
func TestLoggerOutput(t *testing.T) {
type custom struct {
A string
B int8
}
var (
customA = custom{"Foo", 12}
customB = custom{"Foo\nLinebreak", 122}
bb = make([]byte, 10)
tt = time.Time{}
bigint = big.NewInt(100)
nilbig *big.Int
err = fmt.Errorf("Oh nooes it's crap")
lazy = Lazy{Fn: func() interface{} { return "lazy value" }}
smallUint = uint256.NewInt(500_000)
bigUint = &uint256.Int{0xff, 0xff, 0xff, 0xff}
)
out := new(bytes.Buffer)
glogHandler := NewGlogHandler(NewTerminalHandler(out, false))
glogHandler.Verbosity(LevelInfo)
NewLogger(glogHandler).Info("This is a message",
"foo", int16(123),
"bytes", bb,
"bonk", "a string with text",
"time", tt,
"bigint", bigint,
"nilbig", nilbig,
"err", err,
"struct", customA,
"struct", customB,
"ptrstruct", &customA,
"lazy", lazy,
"smalluint", smallUint,
"bigUint", bigUint)
have := out.String()
t.Logf("output %v", out.String())
want := `INFO [11-07|19:14:33.821] This is a message foo=123 bytes="[0 0 0 0 0 0 0 0 0 0]" bonk="a string with text" time=0001-01-01T00:00:00+0000 bigint=100 nilbig=<nil> err="Oh nooes it's crap" struct="{A:Foo B:12}" struct="{A:Foo\nLinebreak B:122}" ptrstruct="&{A:Foo B:12}" lazy="lazy value" smalluint=500,000 bigUint=1,600,660,942,523,603,594,864,898,306,482,794,244,293,965,082,972,225,630,372,095
`
if !bytes.Equal([]byte(have)[25:], []byte(want)[25:]) {
t.Errorf("Error\nhave: %q\nwant: %q", have, want)
}
}
const termTimeFormat = "01-02|15:04:05.000"
func BenchmarkAppendFormat(b *testing.B) {
var now = time.Now()
b.Run("fmt time.Format", func(b *testing.B) {
for i := 0; i < b.N; i++ {
fmt.Fprintf(io.Discard, "%s", now.Format(termTimeFormat))
}
})
b.Run("time.AppendFormat", func(b *testing.B) {
for i := 0; i < b.N; i++ {
now.AppendFormat(nil, termTimeFormat)
}
})
var buf = new(bytes.Buffer)
b.Run("time.Custom", func(b *testing.B) {
for i := 0; i < b.N; i++ {
writeTimeTermFormat(buf, now)
buf.Reset()
}
})
}
func TestTermTimeFormat(t *testing.T) {
var now = time.Now()
want := now.AppendFormat(nil, termTimeFormat)
var b = new(bytes.Buffer)
writeTimeTermFormat(b, now)
have := b.Bytes()
if !bytes.Equal(have, want) {
t.Errorf("have != want\nhave: %q\nwant: %q\n", have, want)
}
}