Question

what is meant by simultaneously access or hierarchial access in computer organisation?

Answer 1

1. Hierarchical is default approach as it is more practical approach in real world scenario .
2. Simultaneous access is like parallel access where we are able to access all levels like level 1, level 2 etc at the same time . This is  im-practical in real world hence Not a default approach .

In hierarchical access when miss in l1 cache , go to l2 cache (means higher level cache) and if not getting in l2, go to l3 , and if not found then access main memory. So basically we go level by level in case of hierarchical.

And read this thread carefully https://gateoverflow.in/130206/co-hierarchical-vs-simultaneous-memory-organization