Potential workaround for poor zstd performance

Performance is still not great, but better

internal/decompress/zstd.go

@@ -1,31 +1,29 @@
 package decompress
 
 import (
-	"bytes"
 	"io"
 
 	"github.com/klauspost/compress/zstd"
 )
 
-type Zstd struct{}
+type Zstd struct {
+	writeToReader *zstd.Decoder
+}
 
 func (z Zstd) Reader(src io.Reader) (io.ReadCloser, error) {
 	r, err := zstd.NewReader(src)
 	return r.IOReadCloser(), err
 }
 
-type ZstdDecodeAll struct {
-	rdr *zstd.Decoder
+func (z Zstd) Resetable() bool { return true }
+
+func (z Zstd) Reset(old, src io.Reader) error {
+	return old.(*zstd.Decoder).Reset(src)
 }
 
-func (z *ZstdDecodeAll) Reader(src io.Reader) (io.ReadCloser, error) {
-	if z.rdr == nil {
-		z.rdr, _ = zstd.NewReader(nil)
+func (z *Zstd) Decode(in []byte) (out []byte, err error) {
+	if z.writeToReader == nil {
+		z.writeToReader, _ = zstd.NewReader(nil)
 	}
-	data, err := io.ReadAll(src)
-	if err != nil {
-		return nil, err
-	}
-	out, err := z.rdr.DecodeAll(data, nil)
-	return io.NopCloser(bytes.NewReader(out)), err
+	return z.writeToReader.DecodeAll(in, nil)
 }