Reply to post: Re: Can you clarify?

Meltdown, Spectre: The password theft bugs at the heart of Intel CPUs

eldakka Silver badge

Re: Can you clarify?

Out-of-order execution

In computer engineering, out-of-order execution (or more formally dynamic execution) is a paradigm used in most high-performance microprocessors to make use of instruction cycles that would otherwise be wasted by a certain type of costly delay.


In 1990s, out-of-order execution became more common, and was featured in the IBM/Motorola PowerPC 601 (1993), Fujitsu/HAL SPARC64 (1995), Intel Pentium Pro (1995), MIPS R10000 (1996), HP PA-8000 (1996), AMD K5 (1996) and DEC Alpha 21264 (1998). Notable exceptions to this trend include the Sun UltraSPARC, HP/Intel Itanium, Transmeta Crusoe, Intel Atom until Silvermont Architecture, and the IBM POWER6.


The Intel 'Core' architecture (i3's, i5's, i7's etc) are basically a derivation of the Pentium Pro that, as per the referenced wikipedia page, introduced out-of-order execution in 1995.

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