@@ -10,19 +10,20 @@ import (
1010
1111"github.com/coder/coder/v2/testutil"
1212"github.com/google/uuid"
13- "github.com/spf13/afero"
1413"github.com/stretchr/testify/require"
1514"golang.org/x/sync/errgroup"
1615)
1716
18- func TestTryAgain (t * testing.T ) {
17+ func TestConcurrency (t * testing.T ) {
18+ t .Parallel ()
19+
1920var fetches atomic.Int64
2021c := newTestCache (func (_ context.Context ,_ uuid.UUID ) (fs.FS ,error ) {
2122fetches .Add (1 )
2223// Wait long enough before returning to make sure that all of the goroutines
2324// will be waiting in line, ensuring that no one duplicated a fetch.
2425time .Sleep (testutil .IntervalMedium )
25- return afero . NewIOFS ( afero . NewMemMapFs ()) ,nil
26+ return nil ,nil
2627})
2728
2829batches := 1000
@@ -32,7 +33,8 @@ func TestTryAgain(t *testing.T) {
3233}
3334
3435// Call Acquire with a unique ID per batch, many times per batch, with many
35- // batches all in parallel. This gives us
36+ // batches all in parallel. This is pretty much the worst-case scenario:
37+ // thousands of concurrent reads, with both warm and cold loads happening.
3638batchSize := 10
3739for _ ,g := range groups {
3840id := uuid .New ()
@@ -50,6 +52,41 @@ func TestTryAgain(t *testing.T) {
5052require .Equal (t ,int64 (batches ),fetches .Load ())
5153}
5254
55+ func TestRelease (t * testing.T ) {
56+ t .Parallel ()
57+
58+ c := newTestCache (func (_ context.Context ,_ uuid.UUID ) (fs.FS ,error ) {
59+ return nil ,nil
60+ })
61+
62+ batches := 100
63+ ids := make ([]uuid.UUID ,0 ,batches )
64+ for range batches {
65+ ids = append (ids ,uuid .New ())
66+ }
67+
68+ // Acquire a bunch of references
69+ batchSize := 10
70+ for _ ,id := range ids {
71+ for range batchSize {
72+ c .Acquire (t .Context (),id )
73+ }
74+ }
75+
76+ // Make sure cache is fully loaded
77+ require .Equal (t ,len (c .data ),batches )
78+
79+ // Now release all of the references
80+ for _ ,id := range ids {
81+ for range batchSize {
82+ c .Release (id )
83+ }
84+ }
85+
86+ // ...and make sure that the cache has emptied itself.
87+ require .Equal (t ,len (c .data ),0 )
88+ }
89+
5390func newTestCache (fetcher func (context.Context , uuid.UUID ) (fs.FS ,error ))Cache {
5491return Cache {
5592lock : sync.Mutex {},