mirror/gohugoio-hugo
1
0
Fork 0
mirror of https://github.com/gohugoio/hugo.git synced 2024-05-11 05:54:58 +00:00
Code Issues Releases Activity

tpl/partials: Make sure a cached partial is invoked only once

Browse Source 
This commit revises the locking strategy for `partialCached`. We have added a benchmark that may be a little artificial, but it should at least show that we're not losing any performance over this:

```bash
name              old time/op    new time/op    delta
IncludeCached-10    12.2ms ± 2%    11.3ms ± 1%   -7.36%  (p=0.029 n=4+4)

name              old alloc/op   new alloc/op   delta
IncludeCached-10    7.17MB ± 0%    5.09MB ± 0%  -29.00%  (p=0.029 n=4+4)

name              old allocs/op  new allocs/op  delta
IncludeCached-10      128k ± 1%       70k ± 0%  -45.42%  (p=0.029 n=4+4)
```

This commit also revises the template metrics hints logic a little, and add a test for it, which output is currently this:

```bash
 cumulative       average       maximum      cache  percent  cached  total
       duration      duration      duration  potential   cached   count  count  template
     ----------      --------      --------  ---------  -------  ------  -----  --------
      163.334µs     163.334µs     163.334µs          0        0       0      1  index.html
       23.749µs       5.937µs      19.916µs         25       50       2      4  partials/dynamic1.html
        9.625µs       4.812µs        6.75µs        100       50       1      2  partials/static1.html
        7.625µs       7.625µs       7.625µs        100        0       0      1  partials/static2.html
```

Some notes:

* The duration now includes the cached invocations (which should be very short)
* A cached template gets executed once before it gets cached, so the "percent cached" will never be 100.

Fixes #4086
Fixes #9506
This commit is contained in:
Bjørn Erik Pedersen
2022-02-16 10:26:42 +01:00
parent 26a5e89faa
commit 0927cf739f
6 changed files with 171 additions and 14 deletions
Download Patch File Download Diff File Expand all files Collapse all files

29
tpl/partials/partials.go
View File

@@ -24,6 +24,7 @@ import (
"reflect"
"strings"
"sync"
"time"
texttemplate "github.com/gohugoio/hugo/tpl/internal/go_templates/texttemplate"
@@ -44,6 +45,13 @@ type partialCacheKey struct {
variant interface{}
}
func (k partialCacheKey) templateName() string {
if !strings.HasPrefix(k.name, "partials/") {
return "partials/" + k.name
}
return k.name
}
// partialCache represents a cache of partials protected by a mutex.
type partialCache struct {
sync.RWMutex
@@ -211,6 +219,7 @@ func createKey(name string, variants ...interface{}) (partialCacheKey, error) {
var errUnHashable = errors.New("unhashable")
func (ns *Namespace) getOrCreate(key partialCacheKey, context interface{}) (result interface{}, err error) {
start := time.Now()
defer func() {
if r := recover(); r != nil {
err = r.(error)
@@ -226,9 +235,20 @@ func (ns *Namespace) getOrCreate(key partialCacheKey, context interface{}) (resu
ns.cachedPartials.RUnlock()
if ok {
if ns.deps.Metrics != nil {
ns.deps.Metrics.TrackValue(key.templateName(), p, true)
// The templates that gets executed is measued in Execute.
// We need to track the time spent in the cache to
// get the totals correct.
ns.deps.Metrics.MeasureSince(key.templateName(), start)
}
return p, nil
}
ns.cachedPartials.Lock()
defer ns.cachedPartials.Unlock()
var name string
name, p, err = ns.include(key.name, context)
if err != nil {
@@ -236,14 +256,7 @@ func (ns *Namespace) getOrCreate(key partialCacheKey, context interface{}) (resu
}
if ns.deps.Metrics != nil {
ns.deps.Metrics.TrackValue(name, p, true)
}
ns.cachedPartials.Lock()
defer ns.cachedPartials.Unlock()
// Double-check.
if p2, ok := ns.cachedPartials.p[key]; ok {
return p2, nil
ns.deps.Metrics.TrackValue(name, p, false)
}
ns.cachedPartials.p[key] = p