Appendix A MIPS Multithreading
Multithreading hardware was 2004-2005’s “Next Big Thing” in computers. Not so in 2006: Virtualization looks like this year’s NBT, a crown it last held around 1975–1980. The crest of the multithreading hype wave has gone past, and multithreading still looks pretty important.
So let’s attempt to define what it is, and then why it’s useful. We’ll use “multithreading” without the hyphen, and use the abbreviation “MT” to refer to the MIPS32/64 architecture extension (the MT ASE).
A thread is a sequence of instructions executed in the order the programmer intended.
That seems a bit simple, really, though it leaves a “thread” as a thing that is probably pretty tangled (there are muddied paths ...