Google Tensor

Google Tensor is a series of ARM64-based system-on-chip (SoC) processors designed by Google for its Pixel devices. It was originally conceptualized in 2016, following the introduction of the first Pixel smartphone, though actual developmental work did not become in full swing until 2020. The first-generation Tensor chip debuted on the Pixel 6 smartphone series in 2021, and were succeeded by the Tensor G2 chip in 2022 and G3 in 2023. Tensor has been generally well received by critics.

Development

Background 
Development on a Google-designed system-on-chip (SoC) first began in April 2016, after the introduction of the company's first Pixel smartphone, although Google CEO Sundar Pichai and hardware chief Rick Osterloh agreed it would likely take an extended period of time before the product was ready. The next year, the company's hardware division assembled a team of 76 semiconductor researchers specializing in artificial intelligence (AI) and machine learning (ML), which has since increased in size, to work on the chip. Beginning in 2017, Google began to include custom-designed co-processors in its Pixel smartphones, namely the Pixel Visual Core on the Pixel 2 and Pixel 3 series and the Pixel Neural Core on the Pixel 4 series.

By April 2020, the company had made "significant progress" toward a custom ARM-based processor for its Pixel and Chromebook devices, codenamed "Whitechapel". At Google parent company Alphabet Inc.'s quarterly earnings investor call that October, Pichai expressed excitement at the company's "deeper investments" in hardware, which some interpreted as an allusion to Whitechapel. The Neural Core was not included on the Pixel 5, which was released in 2020; Google explained that the phone's Snapdragon 765G SoC already achieved the camera performance the company had been aiming for. In April 2021, it was reported that Whitechapel would power Google's next Pixel smartphones. Google was also in talks to acquire Nuvia prior to its acquisition by Qualcomm in 2021.

Google officially unveiled the chip, named Tensor, in August, as part of a preview of its Pixel 6 and Pixel 6 Pro smartphones. Previous Pixel smartphones had used Qualcomm Snapdragon chips, with 2021's Pixel 5a being the final Pixel phone to do so. Pichai later obliquely noted that the development of Tensor and the Pixel 6 resulted in more off-the-shelf solutions for Pixel phones released in 2020 and early 2021. In September 2022, The Verge reported that a Tensor-powered successor to the Pixelbook laptop with a planned 2023 release had been canceled due to cost-cutting measures.

Design 
"Tensor" is a reference to Google's TensorFlow and Tensor Processing Unit technologies, and the chip is developed by the Google Silicon team housed within the company's hardware division, led by vice president and general manager Phil Carmack alongside senior director Monika Gupta, in conjunction with the Google Research division.

Tensor's microarchitecture consists of two large cores, two medium cores, and four small cores; this arrangement is unusual for octa-core SoCs, which typically only have one large core. Carmack explained that this was so Tensor could remain efficient at intense workloads by running both large cores simultaneously at a low frequency to manage the various co-processors. Osterloh has stated that Tensor's performance is difficult to quantify using synthetic benchmarks, but should instead be characterized by the many ML capabilities it enables, such as advanced speech recognition, real-time language translation, the ability to unblur photographs, and HDR-like frame-by-frame processing for videos.

Models

Original 
The first-generation Tensor chip debuted on the Pixel 6 and Pixel 6 Pro, which were officially announced in October 2021 at the Pixel Fall Launch event. It was later reused for the Pixel 6a, a mid-range variant of the Pixel 6 series which was announced in July 2022. Despite being marketed as developed by Google, close-up examinations revealed that the chip contains numerous similarities with Samsung's Exynos series.

G2 
A second-generation Tensor chip was in development by October 2021, codenamed "Cloudripper". At the annual Google I/O keynote in July 2022, Google announced that the chip would debut on the Pixel 7 and Pixel 7 Pro smartphones, which were officially announced on October 6 at the annual Made by Google event. The chip is marketed as "Google Tensor G2". The chip was also used to power the Pixel 7a, Pixel Fold foldable smartphone, and Pixel Tablet which was unveiled in May 2023 during the annual I/O keynote. It is the first Android SoC not to support 32-bit applications, instead only supporting 64-bit apps.

G3 
Samsung had begun testing Tensor G3 by August 2022, codenamed "Zuma" and expected to debut the following year. Announced in October 2023, the chip was used to power the Pixel 8 and Pixel 8 Pro.

Future 
The Information reported in July 2023 that Google had suspended development on Tensor G4, codenamed "Redondo", that had been intended to be released in 2024, due to the Google Silicon team missing a 2022 deadline for trial production to begin. Instead, the company had initiated development on Tensor G5, codenamed "Laguna", which was to be designed fully in-house, manufactured by TSMC instead of Samsung, and built on TSMC's 3 nm process.

Reception 
At launch, Tensor was well received. Philip Michaels of Tom's Guide praised the Pixel 6 and Pixel 6 Pro's Tensor-powered features and video enhancements, as did Marques Brownlee and Wired Julian Chokkattu. Chokkattu's colleague Lily Hay Newman also highlighted the chip's security capabilities, declaring them Tensor's strongest selling point. Jacon Krol of CNN Underscored wrote that Tensor delivered "some of the most fluid and fastest performance" on a smartphone, though Android Authority Jimmy Westenberg was ambivalent. Ryne Hager of Android Police thought the chip's performance was acceptable to the everyday user, but was disappointed that Google did not offer more years of Android updates given it was no longer bound by Qualcomm's contractual terms. TechRadar reviewer James Peckham commended Tensor as a "standout feature", though his colleague David Lumb described the chip's performance as "strong but not class-leading".

See also 
 Apple silicon

References 

ARM-based systems on chips
Computer-related introductions in 2021
Google hardware