Re: Efficiency of in-order vs. OoO

Scott Lurndal wrote:

Terje Mathisen <terje.mathisen@tmsw.no> writes:

Having reverse engineered the original Pentium EMON counters I got a
meeting with Intel about their next cpu (the PentiumPro), what I was
told about the Pentium was that this chip was the first one which was
too complicated to create/sell an In-Circuit Emulator (ICE) version, so
instead they added a bunch of counters for near-zero overhead monitoring
and depended on a bit-serial read-out when they needed to dump all state
for debugging. (I have forgotten the proper term for that interface! :-( )

 Scan chains.   The modern interface to scan chains (which we used on the
mainframes in the late 70's/early 80') is JTAG.
 

Thanks!
JTAG was indeed the term as was looking for (and not remembering). Maybe I'm getting old?
Terje
--
- <Terje.Mathisen at tmsw.no>
"almost all programming can be viewed as an exercise in caching"