change logging lovel to debug for failed read in compaction

pkg/vfs/compact.go

@@ -79,7 +79,7 @@ func Compact(conf chunk.Config, store chunk.ChunkStore, slices []meta.Slice, chu
 			l := utils.Min(conf.BlockSize, int(s.Len)-read)
 			p := chunk.NewOffPage(l)
 			if err := readSlice(store, &s, p, read); err != nil {
-				logger.Infof("can't compact chunk %d, retry later, read %d: %s", chunkid, i, err)
+				logger.Debugf("can't compact chunk %d, retry later, read %d: %s", chunkid, i, err)
 				p.Release()
 				writer.Abort()
 				return err