Tick–tock model

Tick–tock was a production model adopted in 2007 by chip manufacturer Intel. Under this model, every new process technology was first used to manufacture a die shrink of a proven microarchitecture (tick), followed by a new microarchitecture on the now-proven process (tock). It was replaced by the process–architecture–optimization model, which was announced in 2016 and is like a tick–tock cycle followed by an optimization phase. More generally, tick–tock is an engineering model which refreshes one half of a binary system each release cycle.

Every "tick" represented a shrinking of the process technology of the previous microarchitecture (with minor changes, commonly to the caches, and rarely introducing new instructions, as with Broadwell in late 2014) and every "tock" designated a new microarchitecture. These occurred roughly every year to 18 months.

Due to the slowing rate of process improvements, in 2014 Intel created a "tock refresh" of a tock in the form of a smaller update to the microarchitecture not considered a new generation in and of itself. In March 2016, Intel announced in a Form 10-K report that it would always do this in future, deprecating the tick–tock cycle in favor of a three-step process–architecture–optimization model, under which three generations of processors are produced under a single manufacturing process, with the third generation out of three focusing on optimization.

After introducing the Skylake architecture on a 14 nm process in 2015, its first optimization was Kaby Lake in 2016. Intel then announced a second optimization, Coffee Lake, in 2017 making a total of four generations at 14 nm before the Palm Cove die shrink to 10 nm in 2018.

With Silvermont Intel tried to start Tick-Tock in Atom architecture but problems with the 10 nm process did not allow to do this. In the table below instead of Tick-Tock steps Process-Architecture-Optimization are used. There is no official confirmation that Intel uses Process-Architecture-Optimization for Atom but it allows us to understand what changes happened in each generation.

Note: There is further the Xeon Phi. It has up to now undergone four development steps with a current top model that got the code name Knights Landing (shortcut: KNL; the predecessor code names all had the leading term Knights in their name) that is derived from the Silvermont architecture as used for the Intel Atom series but realized in a shrunk 14 nm (FinFET) technology. In 2018, Intel announced that Knights Landing and all further Xeon Phi CPU models were discontinued. However, Intel's Sierra Forest and subsequent Atom-based Xeon CPUs are likely a spiritual successor to Xeon Phi.

• List of Intel CPU microarchitectures
• Speculative execution CPU vulnerabilities

• "Intel Tick–Tock Model of Architecture & Silicon Cadence". intel.com. Intel Corporation.
• Intel Tick–Tock Model at IDF 2009, Anandtech.com
• "Intel Tick–Tock Model at IDF 2011" (PDF). intel.com. Intel Corporation. p. 21.