As you now MLS was a traditional type of route caching mechanism that was used on older hardware/software. It was also called as route once switch many forwarding.
CEF cisco epress forwarding is mutually exclusinve of MLS as it has a different way to work. With the advent of CEf, the routing table ( l3 FIB table forwarding information base) and adjaceny table(l2) gets download on the hardware and does the L3 switching. Its is done in hardware so no performance issue.
No, CEF is simply a route caching mechanism. So although CEF does not directly imply hardware switching, this IS the case for switch platforms under normal operation. For routers, CEF based forwarding is done under interrupt. In certain circumstances, CEF forwarding on a switch can also occur under interrupt (Such as if the TCAM FIB is full, for example)
Here's a troubleshooting document on 6500 CEF that may give you some more clarity on it.
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...