change block size cache prefetching to be sharded based on only one character
@@ -24,7 +24,7 @@ func (c *blockSizeCache) close() error {
func (c *blockSizeCache) getSize(blockID string) (int64, error) {
c.mu.Lock()
size, ok := c.cache[blockID]
- prefix := blockID[0:2]
+ prefix := blockID[0:1]
complete := c.completed[prefix]
if !c.populated[prefix] {
