hugo/metrics/metrics.go
Cameron Moore d16228334d metrics: Add cached count tracking
Track cached partial executions and display more useful info when
showing the hints output. Also group cache hints and counters together
to the right of the timing measurements.

Sample output:

     cumulative       average       maximum      cache  percent  cached  total
       duration      duration      duration  potential   cached   count  count  template
     ----------      --------      --------  ---------  -------  ------  -----  --------
       2.6973ms     674.325µs       857.3µs          0        0       0      4  _internal/_default/rss.xml
       2.6295ms     657.375µs       861.3µs          0        0       0      4  _default/single.html
       1.2563ms     314.075µs       381.5µs          0        0       0      4  news/single.html
        799.2µs       399.6µs       573.3µs          0        0       0      2  _internal/_default/sitemap.xml
        667.3µs       66.73µs       238.6µs         84        0       0     10  partials/header.html
        656.7µs      328.35µs       459.4µs          0        0       0      2  _default/list.html
        479.7µs       47.97µs         158µs         92        0       0     10  partials/head.html
        323.3µs       323.3µs       323.3µs          0        0       0      1  _internal/alias.html
        200.7µs       200.7µs       200.7µs          0        0       0      1  _internal/_default/sitemapindex.xml
         36.1µs       6.016µs        32.6µs        100       33       2      6  partials/footer.html
         27.4µs        13.7µs        26.7µs          0        0       0      2  index.html

Fixes #8375
2022-02-16 10:05:17 +01:00

289 lines
7 KiB
Go

// Copyright 2017 The Hugo Authors. All rights reserved.
//
// 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 metrics provides simple metrics tracking features.
package metrics
import (
"fmt"
"io"
"math"
"reflect"
"sort"
"strconv"
"strings"
"sync"
"time"
"github.com/gohugoio/hugo/common/types"
"github.com/gohugoio/hugo/compare"
"github.com/gohugoio/hugo/helpers"
)
// The Provider interface defines an interface for measuring metrics.
type Provider interface {
// MeasureSince adds a measurement for key to the metric store.
// Used with defer and time.Now().
MeasureSince(key string, start time.Time)
// WriteMetrics will write a summary of the metrics to w.
WriteMetrics(w io.Writer)
// TrackValue tracks the value for diff calculations etc.
TrackValue(key string, value interface{}, cached bool)
// Reset clears the metric store.
Reset()
}
type diff struct {
baseline interface{}
count int
simSum int
}
func (d *diff) add(v interface{}) *diff {
if types.IsNil(d.baseline) {
d.baseline = v
d.count = 1
d.simSum = 100 // If we get only one it is very cache friendly.
return d
}
adder := howSimilar(v, d.baseline)
d.simSum += adder
d.count++
return d
}
// Store provides storage for a set of metrics.
type Store struct {
calculateHints bool
metrics map[string][]time.Duration
mu sync.Mutex
diffs map[string]*diff
diffmu sync.Mutex
cached map[string]int
cachedmu sync.Mutex
}
// NewProvider returns a new instance of a metric store.
func NewProvider(calculateHints bool) Provider {
return &Store{
calculateHints: calculateHints,
metrics: make(map[string][]time.Duration),
diffs: make(map[string]*diff),
cached: make(map[string]int),
}
}
// Reset clears the metrics store.
func (s *Store) Reset() {
s.mu.Lock()
s.metrics = make(map[string][]time.Duration)
s.mu.Unlock()
s.diffmu.Lock()
s.diffs = make(map[string]*diff)
s.diffmu.Unlock()
s.cachedmu.Lock()
s.cached = make(map[string]int)
s.cachedmu.Unlock()
}
// TrackValue tracks the value for diff calculations etc.
func (s *Store) TrackValue(key string, value interface{}, cached bool) {
if !s.calculateHints {
return
}
s.diffmu.Lock()
d, found := s.diffs[key]
if !found {
d = &diff{}
s.diffs[key] = d
}
d.add(value)
s.diffmu.Unlock()
if cached {
s.cachedmu.Lock()
s.cached[key] = s.cached[key] + 1
s.cachedmu.Unlock()
}
}
// MeasureSince adds a measurement for key to the metric store.
func (s *Store) MeasureSince(key string, start time.Time) {
s.mu.Lock()
s.metrics[key] = append(s.metrics[key], time.Since(start))
s.mu.Unlock()
}
// WriteMetrics writes a summary of the metrics to w.
func (s *Store) WriteMetrics(w io.Writer) {
s.mu.Lock()
results := make([]result, len(s.metrics))
var i int
for k, v := range s.metrics {
var sum time.Duration
var max time.Duration
diff, found := s.diffs[k]
cacheFactor := 0
if found {
cacheFactor = int(math.Floor(float64(diff.simSum) / float64(diff.count)))
}
for _, d := range v {
sum += d
if d > max {
max = d
}
}
avg := time.Duration(int(sum) / len(v))
cacheCount := s.cached[k]
results[i] = result{key: k, count: len(v), max: max, sum: sum, avg: avg, cacheCount: cacheCount, cacheFactor: cacheFactor}
i++
}
s.mu.Unlock()
if s.calculateHints {
fmt.Fprintf(w, " %13s %12s %12s %9s %7s %6s %5s %s\n", "cumulative", "average", "maximum", "cache", "percent", "cached", "total", "")
fmt.Fprintf(w, " %13s %12s %12s %9s %7s %6s %5s %s\n", "duration", "duration", "duration", "potential", "cached", "count", "count", "template")
fmt.Fprintf(w, " %13s %12s %12s %9s %7s %6s %5s %s\n", "----------", "--------", "--------", "---------", "-------", "------", "-----", "--------")
} else {
fmt.Fprintf(w, " %13s %12s %12s %5s %s\n", "cumulative", "average", "maximum", "", "")
fmt.Fprintf(w, " %13s %12s %12s %5s %s\n", "duration", "duration", "duration", "count", "template")
fmt.Fprintf(w, " %13s %12s %12s %5s %s\n", "----------", "--------", "--------", "-----", "--------")
}
sort.Sort(bySum(results))
for _, v := range results {
if s.calculateHints {
fmt.Fprintf(w, " %13s %12s %12s %9d %7.f %6d %5d %s\n", v.sum, v.avg, v.max, v.cacheFactor, float64(v.cacheCount)/float64(v.count)*100, v.cacheCount, v.count, v.key)
} else {
fmt.Fprintf(w, " %13s %12s %12s %5d %s\n", v.sum, v.avg, v.max, v.count, v.key)
}
}
}
// A result represents the calculated results for a given metric.
type result struct {
key string
count int
cacheCount int
cacheFactor int
sum time.Duration
max time.Duration
avg time.Duration
}
type bySum []result
func (b bySum) Len() int { return len(b) }
func (b bySum) Swap(i, j int) { b[i], b[j] = b[j], b[i] }
func (b bySum) Less(i, j int) bool { return b[i].sum > b[j].sum }
// howSimilar is a naive diff implementation that returns
// a number between 0-100 indicating how similar a and b are.
func howSimilar(a, b interface{}) int {
t1, t2 := reflect.TypeOf(a), reflect.TypeOf(b)
if t1 != t2 {
return 0
}
if t1.Comparable() && t2.Comparable() {
if a == b {
return 100
}
}
as, ok1 := types.TypeToString(a)
bs, ok2 := types.TypeToString(b)
if ok1 && ok2 {
return howSimilarStrings(as, bs)
}
if ok1 != ok2 {
return 0
}
e1, ok1 := a.(compare.Eqer)
e2, ok2 := b.(compare.Eqer)
if ok1 && ok2 && e1.Eq(e2) {
return 100
}
pe1, pok1 := a.(compare.ProbablyEqer)
pe2, pok2 := b.(compare.ProbablyEqer)
if pok1 && pok2 && pe1.ProbablyEq(pe2) {
return 90
}
h1, h2 := helpers.HashString(a), helpers.HashString(b)
if h1 == h2 {
return 100
}
return 0
}
// howSimilar is a naive diff implementation that returns
// a number between 0-100 indicating how similar a and b are.
// 100 is when all words in a also exists in b.
func howSimilarStrings(a, b string) int {
if a == b {
return 100
}
// Give some weight to the word positions.
const partitionSize = 4
af, bf := strings.Fields(a), strings.Fields(b)
if len(bf) > len(af) {
af, bf = bf, af
}
m1 := make(map[string]bool)
for i, x := range bf {
partition := partition(i, partitionSize)
key := x + "/" + strconv.Itoa(partition)
m1[key] = true
}
common := 0
for i, x := range af {
partition := partition(i, partitionSize)
key := x + "/" + strconv.Itoa(partition)
if m1[key] {
common++
}
}
return int(math.Floor((float64(common) / float64(len(af)) * 100)))
}
func partition(d, scale int) int {
return int(math.Floor((float64(d) / float64(scale)))) * scale
}