AI processing at the edge

Read a couple of articles over the past few weeks (TechCrunch: Google is making a fast, specialized TPU chip for edge devices … and IEEE Spectrum: Two startups use processing in flash for AI at the edge) about chips for AI at the IoT edge.

The two startups, Syntiant and Mythic, are moving to analog only or analog-digital solutions to provide AI processing needed at the edge while Google is taking their TPU technology to the edge.  We have written about Google’s TPU before (see: TPU and hardware vs. software  innovation (round 3) post).

The major challenge in AI processing at the edge is power consumption. Both  startups attack the power problem by using flash and other analog circuitry to provide power efficient compute.

Google attacked the power problem with their original TPU by reducing computational precision from 64- to 8-bits. By reducing transistor counts, they lowered power requirements proportionally.

AI today is based on neural networks (NN), that connect simulated neurons via simulated synapses with weights attached to indicate whether to boost or decrease the signal being transmitted. AI learning is done by setting those weights and creating the connections between simulated neurons and the synapses.  So learning is setting weights and establishing connections. Actual inferences (using AI to do something) is a process of exciting input simulated neurons/synapses and letting the signal flow through the NN with each weight being used to determine output(s).

AI with standard compute

The problem with doing AI learning or inferencing with normal CPUs or even CUDAs is that the NN does thousands if not millions of  multiplication-accumulation actions at each simulated synapse-neuron connection. Doing all these multiplication-accumulation takes power. CPUs and CUDAs can do these sorts of operations on 32 or 64 bit numbers or even floating point but it still takes power.

AI processing power

AI processing power is measured in trillions of (accumulate-multiply) operations per second per watt (TOPS/W). Mythic believes it can perform 4 TOPS/W and Syntiant says it can do 20 TOPS/W. In comparison, the NVIDIA Volta V100 can do about 0.4 TOPS/W (according to the article). Although  comparing Syntiant-Mythic TOPS to NVIDIA TOPS is a little like comparing apples to oranges.

A current Intel Xeon Platinum 8180M (2.5Ghz, 28 Core processors, 205 W) can probably do (assuming one multiplication-accumulation per hertz) about 2.5 Billion X 28 Cores = 70 Billion Ops Second/205 W or 0.3 GOPS/W (source: Platinum 8180M Data sheet).

As for Google’s TPU TOPS/W, TPU2 is rated at 45 GFLOPS/chip and best guess for power consumption is between 160W and 200W, let’s say 180W. With power at that level, TPU2 should hit 0.25 GFLOPS/W.  TPU3 is coming out with 8X the power but it uses water cooling (read LOTS MORE POWER).

Nonetheless, it appears that Mythic and Syntiant are one to two orders of magnitude better than the best that NVIDIA and TPU2 can do today and many orders of magnitude better than Intel X86.

Improving TOPS/W

Use NAND, as an analog memory to read, write and hold  NN weights is an easy way to reduce power consumption. Combine that with  analog circuitry that can do multiplication and addition with those flash values and you have a AI NN processor. This way you reduce the need to hold weights in memory and do compute in registers by collapsing both compute and memory into the same componentry.

The major difference between Syntiant and Mythic seems to be the amount of analog circuitry they use. Mythic seems to relegate the analog circuitry to an accelerator while Syntiant has a more extensive use of analog circuitry throughout their chip. Probably why it can perform 5X the TOPS/W of Mythic’s IPU.

IBM and others have been working on neuromorphic chips some of which are analog based and others which are all digital based. We’ve written extensively on IBM and some on MIT’s approaches (for the latest on IBM see: More power efficient deep learning through IBM and PCM, and for MIT see: MIT builds an analog synapse chip) and follow the links there to learn more.

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Special purpose AI hardware is emerging from the labs and finally reaching reality. IBM R&D has been playing with it for a long time. Google is working on TPU3 so there’s no stopping them. And startups are seeing an opening and are taking everyone on. Stay tuned, were in for a good long ride before the someone rises above the crowd and becomes the next chip giant.

Comments?

 

Photo Credit(s): TechCrunch  Google is making a fast, specialized TPU chip for edge devices … article

Introduction to Digital Design Verification at Mythic, Medium.com Article

Images from Google Cloud Platform Blog on the TPU

Two startups use processing in flash for AI at the edge, IEEE Spectrum article courtesy of Mythic

Skyrmion and chiral bobber solitons for racetrack storage

Read an article this week in Science Daily (Magnetic skyrmions: Not the only one of their class; …) about new magnetic structures that could lend themselves to creating a new type of moving, non-volatile storage.  (There’s more information in the press release and the Nature paper [DOI: 10.1038/s41565-018-0093-3], behind a paywall).

Skyrmions and chiral bobbers are both considered magnetic solitons, types of magnetic structures only 10’s of nm wide, that can move around, in sort of a race track configuration.

Delay line memories

Early in computing history, there was a type of memory called a delay line memory which used various mechanisms (mercury, magneto-resistence, capacitors, etc.) arranged along a circular line such as a wire, and had moving pulses of memory that raced around it. .

One problem with delay line memory was that it was accessed sequentially rather than core which could be accessed randomly. When using delay lines to change a bit, one had to wait until the bit came under the read/write head . It usually took microseconds for a bit to rotate around the memory line and delay line memories had a capacity of a few thousand bits 256-512 bytes per line,  in today’s vernacular.

Delay lines predate computers and had been used for decades to delay any electronic or acoustic signal before retransmission.

A new racetrack

Solitons are being investigated to be used in a new form of delay line memory, called racetrack memory. Skyrmions had been discovered a while ago but the existence of chiral bobbers was only theoretical until researchers discovered them in their lab.

Previously, the thought was that one would encode digital data with only skyrmions and spaces. But the discovery of chiral bobbers and the fact that they can co-exist with skyrmions, means that chiral bobbers and skyrmions can be used together in a racetrack fashion to record digital data.  And the fact that both can move or migrate through a material makes them ideal for racetrack storage.

Unclear whether chiral bobbers and skyrmions only have two states or more but the more the merrier for storage. I am assuming that bit density or reliability is increased by having chiral bobbers in the chain rather than spaces.

Unlike disk devices with both rotating media and moving read-write heads, the motion of skyrmion-chiral bobber racetrack storage is controlled by a very weak pulse of current and requires no moving/mechanical parts prone to wear/tear. Moreover, as a solid state devices, racetrack memory is not sensitive to induced/organic vibration or shock,  So, theoretically these devices should have higher reliability than disk devices.

There was no information comparing the new racetrack memory reliability to NAND or 3D Crosspoint/PCM SSDs, but there may be some advantage here as well. I suppose one would need to understand how to miniaturize the read-erase-write head to the right form factor for nm racetracks to understand how it compares.

And I didn’t see anything describing how long it takes to rotate through bits on a skyrmion-chiral bobber racetrack. Of course, this would depend on the number of bits on a racetrack, but some indication of how long it takes one bit to move, one postition on the racetrack would be helpful to see what its rotational latency might be.

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At the moment, reading and writing skyrmions and the newly discovered chiral bobbers takes a lot of advanced equipment and is only done in major labs. As such, I don’t see a skyrmion-chiral bobber racetrack storage device arriving on my desktop anytime soon. But the fact that there’s a long way to go before, we run out of magnetic storage options, even if it is on a chip rather than magnetic media,  is comforting to know. Even if we don’t ever come up with an economical way to produce it.

I wonder if you could synchronize rotational timing across a number of racetrack devices, at least that way you could be reading/erasing/writing a whole byte, word, double word etc, at a time, rather than a single bit.

Comments?

Photo Credit(s): From Experimental observation of chiral magnetic bobbers in B20 Type FeGe paper

From Experimental observation of chiral magnetic bobbers in B20 Type FeGe paper

From Timeline of computer history Magnetoresistive delay lines

From Experimental observation of chiral magnetic bobbers in B20 Type FeGe paper

MIT’s new Navion chip for better Nano drone navigation

Read an article this week in Science Daily (Chip upgrade help’s bee-sized drones navigate) about a recent chip created by MIT, called Navion, that reduces size and power consumption for electronics used in drone navigation. The chip is also documented on MIT’s Navion project homepage and in a technical  paper describing the new VIO (Visual-Inertial Odometry ) Navion chip.

The Navion chip can perform inertial measurement at 52Khz as well as process video streams of 752×480 stereo images at 171 frames per second in a 20 sqmm package consuming only 24mW of power. The chip was fabricated on a 65nm CMOS process line.

Navion is the result of a collaborative design process which optimized electronics required to perform  drone navigation processing. By placing all the memory required for inertial measurement and image analysis and all the processing hardware on the same chip, they have substantially reduced power consumption and space requirements for drone navigation.

Navion architecture

Navion uses a state of the art, non-linear factor graph optimization algorithm to navigate in space.  It doesn’t sound like  DL neural net image recognition but more like a statistical/probabilistic approach to image mapping and place estimation. The chip uses image compression, two stage memory, and sparse linear solver memory to reduce image processing memory requirements from 3.5MB to less than 1MB.

The chip uses 3 inputs: two images (right &  left image) and IMU (inertial management unit sensor) and has one (complex output), its estimate of the current state of where it is on the map.

Navion processing creates and maintains a 3D map using stereo images and provides navigational support to move through that space.  According to the paper, the Navion chip updates the state(s) and sparse 3D map at a KF (Kalman filter) rate of between 16 and 90 fps. Navion also offers configurations options to maximize accuracy, throughput or energy efficiency.

Navion compares well to other navigation electronics

The table shows comparisons of the Navion chip against other traditional navigational systems that use Xeon, ARM or FPGA chips. As far as I can tell it’s either much better or at least on a par with these other larger, more complex, power hungry systems.

Nano drones are coming to our space, sooner than anyone expects.

Comments?

Photo credit(s): System overview from Navion project page (c) 2018 MIT;

Picture of chip with layout  from Navion project page (c) 2018 MIT;

Navion: A Fully Integrated Energy-Efficient Visual-Inertial Odometry Accelerator for Autonomous Navigation of Nano Drones (c) 2018 MIT

Stanford Data Lab students hit the ground running…

Read an article (Students confront the messiness of data) today about Stanford’s Data Lab  and how their students are trained to cleanup and analyze real world data.

The Data Lab teaches two courses the Data Challenge Lab course and the Data Impact Lab course. The Challenge Lab is an introductory course in data gathering, cleanup and analysis. The Impact Lab is where advanced students tackle real world, high impact problems through data analysis.

Data Challenge Lab

Their Data Challenge Lab course is a 10 week course with no pre-requisites that teaches students how to analyze real world data to solve problems.

Their are no lectures. You’re given project datasets and the tools to manipulate, visualize and analyze the data. Your goal is to master the tools, cleanup the data and gather insights from the data. Professors are there to provide one on one help so you can step through the data provided and understand how to use the tools.

In the information provided on their website there were no references and no information about the specific tools used in the Data Challenge Lab to manipulate, visualize and analyze the data. From an outsiders’ viewpoint it would be great to have a list of references or even websites describing the tools being used and maybe the datasets that are accessed.

Data Impact Lab

The Data Impact lab course is an independent study course, whose only pre-req is the Data Challenge Lab.

Here students are joined into interdisplinary teams with practitioner partners to tackle ongoing, real world problems with their new data analysis capabilities.

There is no set time frame for the course and it is a non-credit activity. But here students help to solve real world problems.

Current projects in the Impact lab include:

  • The California Poverty Project  to create an interactive map of poverty in California to supply geographic guidance to aid agencies helping the poor
  • The Zambia Malaria Project to create an interactive map of malarial infestation to help NGOs and other agencies target remediation activity.

Previous Impact Lab projects include: the Poverty Alleviation Project to provide a multi-dimensional index of poverty status for areas in Kenya so that NGOs can use these maps to target randomized experiments in poverty eradication and the Data Journalism Project to bring data analysis tools to breaking stories and other journalistic endeavors.

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Courses like these should be much more widely available. It’s almost the analog to the scientific method, only for the 21st century.

Science has gotten to a point, these days, where data analysis is a core discipline that everyone should know how to do. Maybe it doesn’t have to involve Hadoop but rudimentary data analysis, manipulation, and visualization needs to be in everyone’s tool box.

Data 101 anyone?

Photo Credit(s): Big_Data_Prob | KamiPhuc;

Southbound traffic speeds on Masonic avenue on different dates | Eric Fisher;

Unlucky Haiti (1981-2010) | Jer Thorp;

Bristol Cycling Level by Wards 2011 | Sam Saunders

Information flows everywhere – part 1

Read an article today from Scientific American (Sewage is helping cities flush out the opioid crisis) about how using chemical analysis of wastewater can be used to assess the extent of the opioid crisis in their city.

Wastewater information highway

There’s a lab at ASU (Arizona State University) that chemically analyzes samples of wastewater to determine the amount of drugs that a city’s population excretes. They can provide a near real-time assessment of the proportion of drugs in city sewage and thereby, in a city’s population.

The problem with public drug use surveys and hospital data gathering is that they take time.  Moreover, surveys and hospital data gathering typically come long after drugs problem have become a serious problem in a city’s population.

Wastewater sample drug analysis can be done in a matter of days and can be redone as often as needed. Such data could be used to track intervention activities and see if they have a real impact (positive or negative) on drug use in a population.

Neighborhood health

In addition, by sampling sewage at a neighborhood level, one can gain an assessment of drug problems at any sub-division of a city that’s needed.

The above article talks about an MIT program with Cary, NC (from Biobot.io)  that is designing robots to traverse sewer pipes and analyze wastewater chemical makeup in real time, reporting this back to ground stations around the city.

With such an approach, one could almost zero in (depending on sewer pipe networks) on any neighborhood in a city, target specific interventions at that level and measure impact in (digestion delayed) real time. Doing so, cities or states for that matter, could  experiment with different interventions on a neighborhood by neighborhood basis and gain statistical evidence on drug problem intervention effectiveness.

But, you can analyze wastewater for any number of variables, such as viruses, bacteria, enzymes, etc. Any of which can lead to a better understanding of a population’s health.

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Two things I want to leave you with:

First, public health has had a major impact on human health and has doubled our lifespan in 200 years. All modern cities have water treatment plants today to insure water quality and thereby, have reduced the incidence of cholera and other waterborne epidemics in their cities. Wastewater analysis has the potential for significant improvements in population health monitoring. Just like water treatment, wastewater analysis will someday become common public health practice in modern cities throughout the world.

Second, I was at a conference this week which presented a slide that there was no cold data anymore (Pure//Accelerate 2018). This was in reference to  re-analyzing old, cold data can often lead to insights and process improvements that were not obvious at first glance.

But it’s not just data anymore. Any activity done by man needs to be analyzed for (inherent & invisible) information flows that could be extracted to make the world a better place.

Photo Credit(s):

Random access, DNA object storage system

Read a couple of articles this week Inching closer to a DNA-based file system in ArsTechnica and DNA storage gets random access in IEEE Spectrum. Both of these seem to be citing an article in Nature, Random access in large-scale DNA storage (paywall).

We’ve known for some time now that we can encode data into DNA strings (see my DNA as storage … and Genomic informatics takes off posts).

However, accessing DNA data has been sequential and reading and writing DNA data has been glacial. Researchers have started to attack the sequentiality of DNA data access. The prize, DNA can store 215PB of data in one gram and DNA data can conceivably last millions of years.

Researchers at Microsoft and the University of Washington have come up with a solution to the sequential access limitation. They have used polymerase chain reaction (PCR) primers as a unique identifier for files. They can construct a complementary PCR primer that can be used to extract just DNA segments that match this primer and amplify (replicate) all DNA sequences matching this primer tag that exist in the cell.

DNA data format

The researchers used a Reed-Solomon (R-S) erasure coding mechanism for data protection and encode the DNA data into many DNA strings, each with multiple (metadata) tags on them. One of tags is the PCR primer tag header, another tag indicates the position of the DNA data segment in the file and an end of data tag that is the same PCR primer tag.

The PCR primer tag was used as sort of a file address. They could configure a complementary PCR tag to match the primer tag of the file they wanted to access and then use the PCR process to replicate (amplify) only those DNA segments that matched the searched for primer tag.

Apparently the researchers chunk file data into a block of 150 base pairs. As there are 2 complementary base pairs, I assume one bit to one base pair mapping. As such, 150 base pairs or bits of data per segment means ~18 bytes of data per segment. Presumably this is to allow for more efficient/effective encoding of data into DNA strings.

DNA strings don’t work well with replicated sequences of base pairs, such as all zeros. So the researchers created a random sequence of 150 base pairs and XOR the file DNA data with this random sequence to determine the actual DNA sequence to use to encode the data. Reading the DNA data back they need to XOR the data segment with the random string again to reconstruct the actual file data segment.

Not clear how PCR replicated DNA segments are isolated and where they are originally decoded (with a read head). But presumably once you have thousands to millions of copies of a DNA segment,  it’s pretty straightforward to decode them.

Once decoded and XORed, they use the R-S erasure coding scheme to ensure that the all the DNA data segments represent the actual data that was encoded in them. They can then use the position of the DNA data segment tag to indicate how to put the file data back together again.

What’s missing?

I am assuming the cellular data storage system has multiple distinct cells of data, which are clustered together into some sort of organism.

Each cell in the cellular data storage system would hold unique file data and could be extracted and a file read out individually from the cell and then the cell could be placed back in the organism. Cells of data could be replicated within an organism or to other organisms.

To be a true storage system, I would think we need to add:

  • DNA data parity – inside each DNA data segment, every eighth base pair would be a parity for the eight preceding base pairs, used to indicate when a particular base pair in eight has mutated.
  • DNA data segment (block) and file checksums –  standard data checksums, used to verify and correct for double and triple base pair (bit) corruption in DNA data segments and in the whole file.
  • Cell directory – used to indicate the unique Cell ID of the cell, a file [name] to PCR primer tag mapping table, a version of DNA file metadata tags, a version of the DNA file XOR string, a DNA file data R-S version/level, the DNA file length or number of DNA data segments, the DNA data creation data time stamp, the DNA last access date-time stamp,and DNA data modification data-time stamp (these last two could be omited)
  • Organism directory – used to indicate unique organism ID, organism metadata version number, organism unique cell count,  unique cell ID to file list mapping, cell ID creation data-time stamp and cell ID replication count.

The problem with an organism cell-ID file list is that this could be quite long. It might be better to somehow indicate a range or list of ranges of PCR primer tags that are in the cell-ID. I can see other alternatives using a segmented organism directory or indirect organism cell to file lists b-tree, which could hold file name lists to cell-ID mapping.

It’s unclear whether DNA data storage should support a multi-level hierarchy, like file system  directories structures or a flat hierarchy like object storage data, which just has buckets of objects data. Considering the cellular structure of DNA data it appears to me more like buckets and the glacial access seems to be more useful to archive systems. So I would lean to a flat hierarchy and an object storage structure.

Is DNA data is WORM or modifiable? Given the effort required to encode and create DNA data segment storage, it would seem it’s more WORM like than modifiable storage.

How will the DNA data storage system persist or be kept alive, if that’s the right word for it. There must be some standard internal cell mechanisms to maintain its existence. Perhaps, the researchers have just inserted file data DNA into a standard cell as sort of junk DNA.

If this were the case, you’d almost want to create a separate, data  nucleus inside a cell, that would just hold file data and wouldn’t interfere with normal cellular operations.

But doesn’t the PCR primer tag approach lend itself better to a  key-value store data base?

Photo Credit(s): Cell structure National Cancer Institute

Prentice Hall textbook

Guide to Open VMS file applications

Unix Inodes CSE410 Washington.edu

Key Value Databases, Wikipedia By ClescopOwn work, CC BY-SA 4.0, Link

AI reaches a crossroads

There’s been a lot of talk on the extendability of current AI this past week and it appears that while we may have a good deal of runway left on the machine learning/deep learning/pattern recognition, there’s something ahead that we don’t understand.

Let’s start with MIT IQ (Intelligence Quest),  which is essentially a moon shot project to understand and replicate human intelligence. The Quest is attempting to answer “How does human intelligence work, in engineering terms? And how can we use that deep grasp of human intelligence to build wiser and more useful machines, to the benefit of society?“.

Where’s HAL?

The problem with AI’s deep learning today is that it’s fine for pattern recognition, but it doesn’t appear to develop any basic understanding of the world beyond recognition.

Some AI scientists concede that there’s more to human/mamalian intelligence than just pattern recognition expertise, while others’ disagree. MIT IQ is trying to determine, what’s beyond pattern recognition.

There’s a great article in Wired about the limits of deep learning,  Greedy, Brittle, Opaque and Shallow: the Downsides to Deep Learning. The article says deep learning is greedy because it needs lots of data (training sets) to work, it’s brittle because step one inch beyond what’s it’s been trained  to do and it falls down, and it’s opaque because there’s no way to understand how it came to label something the way it did. Deep learning is great for pattern recognition of known patterns but outside of that, there must be more to intelligence.

The limited steps using unsupervised learning don’t show a lot of hope, yet

“Pattern recognition” all the way down…

There’s a case to be made that all mammalian intelligence is based on hierarchies of pattern recognition capabilities.

That is, at a bottom level  human intelligence consists of pattern recognition, such as vision, hearing, touch, balance, taste, etc. systems which are just sophisticated pattern recognition algorithms that label what we are hearing as Bethovan’s Ninth Symphony, tasting as grandma’s pasta sauce, and seeing as the Grand Canyon.

Then, at the next level there’s another pattern recognition(-like) system that takes all these labels and somehow recognizes this scene as danger, romance, school,  etc.

Then, at the next level, human intelligence just looks up what to do in this scene.  Almost as if we have a defined list of action templates that are what we do when we are in danger (fight or flight), in romance (kiss, cuddle or ?), in school (answer, study, view, hide, …), etc.  Almost like a simple lookup table with procedural logic behind each entry

One question for this view is how are these action templates defined and  how many are there. If, as it seems, there’s almost an infinite number of them, how are they selected (some finer level of granularity in scene labeling – romance but only flirting …).

No, it’s not …

But to other scientists, there appears to be more than just pattern recognition(-like) algorithms and lookup and act algorithms, going on inside our brains.

For example, once I interpret a scene surrounding me as in danger, romance, school, etc.,  I believe I start to generate possible action lists which I could take in this domain, and then somehow I select the one to do which makes the most sense in this situation or rather gets me closer to my current goal (whatever that is) in this situation.

This is beyond just procedural logic and involves some sort of memory system, action generative system, goal generative/recollection system, weighing of possible action scripts, etc.

And what to make of the brain’s seemingly infinite capability to explain itself…

Baby intelligence

Most babies understand their parents language(s) and learn to crawl within months after birth. But they haven’t listened to thousands of hours of people talking or crawled thousands of miles.  And yet, deep learning requires even more learning sets in order to label language properly or  learning how to crawl on four appendages. And of course, understanding language and speaking it are two different capabilities. Ditto for crawling and walking.

How does a baby learn to recognize these patterns without TB of data and millions of reinforcements (“Smile for Mommy”, say “Daddy”). And what to make of the, seemingly impossible to contain wanderlust, of any baby given free reign of an area.

These questions are just scratching the surface in what it really means to engineer human intelligence.

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MIT IQ is one attempt to try to answer the question that: assuming we understand how to pattern recognition can be made to work well on today’s computers what else do we need to do to build a more general purpose intelligence.

There are obvious ethical questions on whether we want to engineer a human level of intelligence (see my Existential risks… post). Our main concern is what it does (to humanity) once we achieve it.

But assuming we can somehow contain it for the benefit of humanity, we ought to take another look at just what it entails.

 

Photo Credits:  Tech trends for 2017: more AI …., the Next Silicon Valley website. 

HAL from 2001 a Space Odyssey 

Design software test labeling… 

Exploration in toddlers…, Science Daily website