Ashlee Vance at The Register is reporting that Sun has confirmed that Rock, Sun’s next generation processor due out in the second half of 2008, will include transactional memory.
At its most basic level, TM routes around today’s lock-based programming model where developers use a variety of techniques to stop software threads from accessing shared data at the same time. Rather than assuming that software threads will charge after the same information, TM bets on the notion that in many cases a single software thread will seek a unique chunk of data.
In terms a bit closer to developers’ hearts, you can picture writing code where tens or hundreds of instructions are part of a transaction. The TM technology creates a checkpoint at the start of the transaction and maintains all of the involved instructions until there’s a commit. At that point, you see an all or nothing scenarios where either all the loads and stores go through or none do.