ARM Introduces The Revolutionary Cortex A-73 Mobile Core
In February 2015 ARM announced the Cortex A-72, since then this CPU core has been used in multiple flagship smartphones. However, with increasingly complex apps and features being introduced in the smartphones ARM has just announced its next CPU core, Cortex A-73.
This time around the the design group behind Cortex A-73 is Sofia Antipolis, while the previous ones were designed by Cambridge Group. Maybe a new team is the reason that Cortex A-73 differs drastically from previous iterations.
However, the market is constantly changing in terms of workloads and other factors. There are more complex applications being developed for smartphones, new technologies like Augmented Reality and Virtual Reality are being integrated and other technologies like camera, high resolution displays and video playback formats.
The devices are getting slimmer and slimmer and displays are getting large, and all of this is getting beyond the capabilities of Cortex A-72 to increase performance and reducing the size of components so that they can be fit inside the thermal design power envelop of these thin devices.
The main purpose to design the Cortex A-73 is to increase performance, decrease the power consumption and make use of the latest process nodes, and obviously it is not as simple as it sounds.
The design of Cortex A-73 by Sofia group was started from the scratch and not based on Cortex A-72. The main focus of Cortex A-73 design is to take above mentioned performance and power considerations nd keep the clockspeed up and improve efficiency.
The new design for Cortex A-73 features 2-wide superscalar engine with dual decode, however, the previous Cortex A-72 features triple decode engine. You must be thinking that Higher the number of components, better the performance. Well that is not always true specially not in this situation. ARM has successfully managed to improve the IPC while simplifying the design for its Cortex A-73.
The core is code named “Artemis”, which is designed to be the smallest core with a die size of 0.65mm sq. per core on the 10nm chip.
By using a dual decode engine in Cortex A-73, significant performance and efficiency gains have been observed. The company has implemented the instruction fusion capability that allows multiple instructions to be fused, then these instructions are fetched, decode, executed and write back.
The number of instructions have also been reduced which are required to be split in to Micro-Ops. Highly complex instructions were split in to the Micro-Ops, which increased latency and also the clock cycles required to execute the instruction.
ARM now have reworked its front end, which allows greater efficiency in instruction execution cycle. This increases performance and reduces the complexity the instruction cycle, thus increasing the power efficiency.
The Cortex A-73 can be used with A53 for big or small, thick or thin configurations. The optimal setup for upcoming mid-range mobiles is going to be hex-core unit, which features two A-73 and four A53. This configuration takes about the same die space, however, it not only improves per thread performance but also multi-thread performance too.
So what are your thoughts on this new core? Will it revolutionize the smartphone market? Let us know in the comments.