TrueCloudLab/distribution
13
0
Fork 3
Code Issues 2 Pull requests Projects Releases 2 Packages Wiki Activity Actions

avoid redundant blob fetching

Browse source 
Signed-off-by: baojiangnan <baojn1998@163.com>
This commit is contained in:
baojiangnan 2022-01-20 11:52:34 +08:00 committed by baojiangnan.bjn
parent b56fb385f6
commit 17952924f3
2 changed files with 55 additions and 54 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

85
registry/proxy/proxyblobstore.go
View file

@ -79,35 +79,6 @@ func (pbs *proxyBlobStore) serveLocal(ctx context.Context, w http.ResponseWriter
return true, pbs.localStore.ServeBlob(ctx, w, r, dgst)
}
func (pbs *proxyBlobStore) storeLocal(ctx context.Context, dgst digest.Digest) error {
defer func() {
mu.Lock()
delete(inflight, dgst)
mu.Unlock()
}()
var desc distribution.Descriptor
var err error
var bw distribution.BlobWriter
bw, err = pbs.localStore.Create(ctx)
if err != nil {
return err
}
desc, err = pbs.copyContent(ctx, dgst, bw)
if err != nil {
return err
}
_, err = bw.Commit(ctx, desc)
if err != nil {
return err
}
return nil
}
func (pbs *proxyBlobStore) ServeBlob(ctx context.Context, w http.ResponseWriter, r *http.Request, dgst digest.Digest) error {
served, err := pbs.serveLocal(ctx, w, r, dgst)
if err != nil {
@ -126,6 +97,9 @@ func (pbs *proxyBlobStore) ServeBlob(ctx context.Context, w http.ResponseWriter,
mu.Lock()
_, ok := inflight[dgst]
if ok {
// If the blob has been serving in other requests.
// Will return the blob from the remote store directly.
// TODO Maybe we could reuse the these blobs are serving remotely and caching locally.
mu.Unlock()
_, err := pbs.copyContent(ctx, dgst, w)
return err
@ -133,33 +107,40 @@ func (pbs *proxyBlobStore) ServeBlob(ctx context.Context, w http.ResponseWriter,
inflight[dgst] = struct{}{}
mu.Unlock()
// storeLocalCtx will be independent with ctx, because ctx it used to fetch remote image.
// There would be a situation, that is pulling remote bytes ends before pbs.storeLocal( 'Copy', 'Commit' ...)
// Then the registry fails to cache the layer, even though the layer had been served to client.
storeLocalCtx, cancel := context.WithCancel(context.Background())
go func(dgst digest.Digest) {
defer cancel()
if err := pbs.storeLocal(storeLocalCtx, dgst); err != nil {
dcontext.GetLogger(storeLocalCtx).Errorf("Error committing to storage: %s", err.Error())
}
defer func() {
mu.Lock()
delete(inflight, dgst)
mu.Unlock()
}()
blobRef, err := reference.WithDigest(pbs.repositoryName, dgst)
if err != nil {
dcontext.GetLogger(storeLocalCtx).Errorf("Error creating reference: %s", err)
return
}
if pbs.scheduler != nil && pbs.ttl != nil {
pbs.scheduler.AddBlob(blobRef, *pbs.ttl)
}
}(dgst)
_, err = pbs.copyContent(ctx, dgst, w)
bw, err := pbs.localStore.Create(ctx)
if err != nil {
cancel()
return err
}
// Serving client and storing locally over same fetching request.
// This can prevent a redundant blob fetching.
multiWriter := io.MultiWriter(w, bw)
desc, err := pbs.copyContent(ctx, dgst, multiWriter)
if err != nil {
return err
}
_, err = bw.Commit(ctx, desc)
if err != nil {
return err
}
blobRef, err := reference.WithDigest(pbs.repositoryName, dgst)
if err != nil {
dcontext.GetLogger(ctx).Errorf("Error creating reference: %s", err)
return err
}
if pbs.scheduler != nil && pbs.ttl != nil {
pbs.scheduler.AddBlob(blobRef, *pbs.ttl)
}
return nil
}

24
registry/proxy/proxyblobstore_test.go
View file

@ -336,6 +336,12 @@ func testProxyStoreServe(t *testing.T, te *testEnv, numClients int) {
remoteStats := te.RemoteStats()
var wg sync.WaitGroup
var descHitMap = map[digest.Digest]bool{}
var hitLock sync.Mutex
for _, remoteBlob := range te.inRemote {
descHitMap[remoteBlob.Digest] = true
}
for i := 0; i < numClients; i++ {
// Serveblob - pulls through blobs
@ -362,6 +368,15 @@ func testProxyStoreServe(t *testing.T, te *testEnv, numClients int) {
t.Errorf("Mismatching blob fetch from proxy")
return
}
desc, err := te.store.localStore.Stat(te.ctx, remoteBlob.Digest)
if err != nil {
continue
}
hitLock.Lock()
delete(descHitMap, desc.Digest)
hitLock.Unlock()
}
}()
}
@ -371,11 +386,16 @@ func testProxyStoreServe(t *testing.T, te *testEnv, numClients int) {
t.FailNow()
}
if len(descHitMap) > 0 {
t.Errorf("Expected hit cache at least once, but it turns out that no caches was hit")
t.FailNow()
}
remoteBlobCount := len(te.inRemote)
sbsMu.Lock()
if (*localStats)["stat"] != remoteBlobCount*numClients && (*localStats)["create"] != te.numUnique {
if (*localStats)["stat"] != remoteBlobCount*numClients*2 && (*localStats)["create"] != te.numUnique {
sbsMu.Unlock()
t.Fatal("Expected: stat:", remoteBlobCount*numClients, "create:", remoteBlobCount)
t.Fatal("Expected: stat:", remoteBlobCount*numClients, "create:", remoteBlobCount, "Got: stat:", (*localStats)["stat"], "create:", (*localStats)["create"])
}
sbsMu.Unlock()