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  • ROBERT CROWE: I'm Robert Crowe.

  • And we are here today to talk about production pipelines, ML

  • pipelines.

  • So we're not going to be talking about ML modeling

  • too much or different architectures.

  • This is really all focused about when you have a model

  • and you want to put it into production so that you can

  • offer a product or a service or some internal service

  • within your company, and it's something

  • that you need to maintain over the lifetime

  • of that deployment.

  • So normally when we think about ML,

  • we think about modeling code, because it's

  • the heart of what we do.

  • Modeling and the results that we get from the amazing models

  • that we're producing these days, that's

  • the reason we're all here, the results we can produce.

  • It's what papers are written about, for the most part,

  • overwhelmingly.

  • The majority are written about architectures and results

  • and different approaches to doing ML.

  • It's great stuff.

  • I love it.

  • I'm sure you do too.

  • But when you move to putting something into production,

  • you discover that there are a lot of other pieces

  • that are very important to making that model that you

  • spent a lot of time putting together

  • available and robust over the lifetime of a product

  • or a service that you're going to offer out to the world

  • so that they can experience really

  • the benefits of the model that you've worked on.

  • And those pieces are what TFX is all about.

  • In machine learning, we're familiar with a lot

  • of the issues that we have to deal with,

  • things like where do I get labeled data.

  • How do I generate the labels for the data that I have.

  • I may have terabytes of data, but I need labels for them?

  • Does my label cover the feature space

  • that I'm going to see when I actually

  • run inference against it?

  • Is my dimensionality-- is it minimized?

  • Or can I do more to try to simplify

  • my set, my feature vector, to make my model more efficient?

  • Have I got really the predictive information in the data

  • that I'm choosing?

  • And then we need to think about fairness as well.

  • Are we are we serving all of the customers

  • that we're trying to serve fairly, no matter where they

  • are, or what religion they are, what language they speak,

  • what demographic they might be because you

  • want to serve those people as well as you can?

  • You don't want to unfairly disadvantage people.

  • And we may have rare conditions too, especially in things

  • like health care where we're making

  • a prediction that's going to be pretty important

  • to someone's life.

  • And it maybe on a condition that occurs very rarely.

  • But a big one when you go into production

  • is understanding the data lifecycle.

  • Because once you've gone through that initial training

  • and you've put something into production,

  • that's just the start of the process.

  • You're now going to try to maintain that over a lifetime,

  • and the world changes.

  • Your data changes.

  • Conditions in your domain change.

  • Along with that, you're doing now production software

  • deployment.

  • So you have all of the normal things

  • that you have to deal with any software deployment, things

  • like scalability.

  • Will I need to scale up?

  • Is my solution ready to do that?

  • Can I extend it?

  • Is it something that I can build on?

  • Modularity, best practices, testability.

  • How do I test an ML solution?

  • And security and safety, because we

  • know there are attacks for ML models

  • that are getting pretty sophisticated these days.

  • Google created TFX for us to use.

  • We created it because we needed it.

  • It was not the first production ML framework that we developed.

  • We've actually learned over many years

  • because we have ML all over Google

  • taking in billions of inference requests

  • really on a planet scale.

  • And we needed something that would

  • be maintainable and usable at a very large production

  • scale with large data sets and large loads over a lifetime.

  • So TFX has evolved from earlier attempts.

  • And it is now what most of the products and services at Google

  • use.

  • And now we're also making it available to the world

  • as an open-source product available to you now

  • to use for your production deployments.

  • It's also used by several of our partners

  • and just companies that have adopted TFX.

  • You may have heard talks from some of these at the conference

  • already.

  • And there's a nice quote there from Twitter,

  • where they did an evaluation.

  • They were coming from a Torch-based environment,

  • looked at the whole suite or the whole ecosystem of TensorFlow,

  • and moved everything that they did to TensorFlow.

  • One of the big contributors to that

  • was the availability of TFX.

  • The vision is to provide a platform for everyone to use.

  • Along with that, there's some best practices and approaches

  • that we're trying to really make popular in the world, things

  • like strongly-typed artifacts so that when

  • your different components produce artifacts

  • they have a strong type.

  • Pipeline configuration, workflow execution,

  • being able to deploy on different platforms,

  • different distributed pipeline platforms using

  • different orchestrators, different underlying execution

  • engines--

  • trying to make that as flexible as possible.

  • There are some horizontal layers that

  • tie together the different components in TFX.

  • And we'll talk about components here in a little bit.

  • And we have a demo as well that will show you some of the code

  • and some of the components that we're talking about.

  • The horizontal layers-- an important one there is metadata

  • storage .

  • So each of the components produce and consume artifacts.

  • You want to be able to store those.

  • And you may want to do comparisons across months

  • or years to see how did things change, because change becomes

  • a central theme of what you're going to do in a production

  • deployment.

  • This is a conceptual look at the different parts of TFX.

  • On the top, we have tasks--

  • a conceptual look at tasks.

  • So things like ingesting data or training a model

  • or serving the model.

  • Below that, we have libraries that are available, again,

  • as open-source components that you can leverage.

  • They're leveraged by the components within TFX

  • to do much of what they do.

  • And on the bottom row in orange, and a good color for Halloween,

  • we have the TFX components.

  • And we're going to get into some detail about how your data will

  • flow through the TFX pipeline to go from ingesting data

  • to a finished trained model on the other side.

  • So what is a component?

  • A component has three parts.

  • This is a particular component, but it could be any of them.

  • Two of those parts, the driver and publisher,

  • are largely boilerplate code that you could change.

  • You probably won't.

  • A driver consumes artifacts and begins the execution

  • of your component.

  • A publisher takes the output from the component,

  • puts it back into metadata.

  • The executor is really where the work is

  • done in each of the components.

  • And that's also a part that you can change.

  • So you can take an existing component,

  • override the executor in it, and produce

  • a completely different component that

  • does completely different processing.

  • Each of the components has a configuration.

  • And for TFX, that configuration is written in Python.

  • And it's usually fairly simple.

  • Some of the components are a little more complex.

  • But most of them are just a couple of lines of code

  • to configure.

  • The key essential aspect here that I've alluded to

  • is that there is a metadata store.

  • The component will pull data from that store

  • as it becomes available.

  • So there's a set of dependencies that determine which artifacts

  • that component depends on.

  • It'll do whatever it's going to do.

  • And it's going to write the result back into metadata.

  • Over the lifetime of a model deployment,

  • you start to build a metadata store that

  • is a record of the entire lifetime of your model.

  • And the way that your data has changed,

  • the way your model has changed, the way your metrics have

  • changed, it becomes a very powerful tool.

  • Components communicate through the metadata store.

  • So an initial component will produce an artifact,

  • put it in the metadata store.

  • The components that depend on that artifact

  • will then read from the metadata store

  • and do whatever they're going to do,

  • and put their result into it, and so on.

  • And that's how we flow through the pipeline.

  • So the metadata store I keep talking about.

  • What is it?

  • What does it contain?

  • There's really three kinds of things that it contains.

  • Trained models or just artifacts themselves.

  • They could be trained models, they could be data sets,

  • they could be metrics, they could be splits.

  • There's a number of different types of objects

  • that are in the metadata store.

  • Those are grouped into execution records.

  • So when you execute the pipeline,

  • that becomes an execution run.

  • And the artifacts that are associated with that run

  • are grouped under that execution run.

  • So again, when you're trying to analyze what's

  • been happening with your pipeline,

  • that becomes very important.

  • Also, the lineage of those artifacts--

  • so which artifact was produced by which component,

  • which consumed which inputs, and so on.

  • So that gives us some functionality

  • that becomes very powerful over the lifetime of a model.

  • You can find out which data a model

  • was trained on, for example.

  • If you're comparing the results of two different model

  • trainings that you've done, tracing it

  • back to how the data changed can be really important.

  • And we have some tools that allow you to do that.

  • So TensorBoard for example will allow

  • you to compare the metrics from say a model that you trained

  • six months ago and the model that you just trained

  • now to try to understand.

  • I mean, you could see that it was different, buy why--

  • why was it different.

  • And warm-starting becomes very powerful too,

  • especially when you're dealing with large amounts of data that

  • could take hours or days to process,

  • being able to pull that data from cache.

  • If the inputs haven't changed, rather than rerunning

  • that component every time becomes a very powerful tool

  • as well.

  • So there's a set of standard components

  • that are shipped with TFX.

  • But I want you to be aware from the start

  • that you are not limited to those standard components.

  • This is a good place to start.

  • It'll get you pretty far down the road.

  • But you will probably have needs-- you may or may not--

  • where you need to extend the components that are available.

  • And you can do that.

  • You can do that in a couple of different ways.

  • This is sort of the canonical pipeline that we talk about so

  • on the left, we're ingesting our data.

  • We flow through, we split our data,

  • we calculate some statistics against it.

  • And we'll talk about this in some detail.

  • We then make sure that we don't have problems with our data,

  • and try to understand what types our features are.

  • We do some feature engineering, we train.

  • This probably sounds familiar.

  • If you've ever been through an ML development process,

  • this is mirroring exactly what you always do.

  • Then you're going to check your metrics across that.

  • And we do some deep analysis of the metrics of our model

  • because that becomes very important.

  • And we'll talk about an example of that in a little bit.

  • And then you have a decision because let's assume

  • you already have a model in production

  • and you're retraining it.

  • Or maybe you have a new model that you're training

  • and the question becomes, should I

  • push this new model to production,

  • or is the one I already have better.

  • Many of you have probably had the experience,

  • if you trained a new model and it actually didn't do

  • as well as the old one did.

  • Along with that, we also have the ability

  • to do bulk inference on inference requests.

  • So you may be in a batch request environment.

  • So you're pulling in data in batches

  • and you're running requests against it,

  • and then taking that result and doing something

  • with it, that's a very common use case.

  • This is actually kind of new.

  • We have components to do that as well.

  • This is the Python framework of defining a pipeline.

  • So that's a particular component.

  • It's the transform component and the configuration

  • that you need to use for that.

  • But on a very simple level, that's

  • how you set up components.

  • And in the bottom, you can see there's a list of components

  • that are returned in that call.

  • Those are going to be passed to a runner that

  • runs on top of whatever orchestrator you're using.

  • So a little bit more complex example,

  • a little bit harder to read.

  • Gives you an idea there's several components there.

  • The dependencies between components and the dependencies

  • and artifacts that I just talked about

  • are defined in code like that.

  • So you'll see, for example, that StatisticsGen depends

  • on the output of ExampleGen.

  • So now let's talk about each of the standard components.

  • ExampleGen is where you ingest your data.

  • And it is going to take your data,

  • it's going to convert it to TensorFlow examples.

  • This is actually showing just two input formats,

  • but there's a reasonably long list of input formats

  • that you can have.

  • And it'll also do your splits for you.

  • So you may want just training and eval,

  • or maybe you want a validation split as well.

  • So that's what ExampleGen does.

  • And then it passes the result onto StatisticsGen.

  • StatisticsGen, because we all work with data,

  • we know you need to dive into the data

  • and make sure that you understand the characteristics

  • of your data set.

  • Well, StatisticsGen is all about doing that in an environment

  • where you may be running that many times a day.

  • It also gives you tools to do visualization of your data

  • like this.

  • So for example, that's the trip start hour feature

  • for this particular data set.

  • And just looking at that, just looking at the histogram,

  • tells me a lot about an area that I need to focus on.

  • The 6 o'clock hour, I have very little data.

  • So I want to go out and get some more data.

  • Because if I try to use that and I run inference requests

  • at 6:00 AM, it's going to be overgeneralizing.

  • So I don't want that.

  • SchemaGen is looking at the types of your features.

  • So it's trying to decide is it a float, is it an int, is it

  • a categorical feature.

  • And if it's a categorical feature,

  • what are the valid categories?

  • So SchemaGen tries to infer that.

  • But you as a data scientist need to make sure

  • that it did the job correctly.

  • So you need to review that and make any fixes

  • that you need to make.

  • ExampleValidator then takes those two results,

  • the SchemaGen and StatisticsGen, and it looks

  • for problems with your data.

  • So it's going to look for things like missing values,

  • values that are zero and shouldn't

  • be zero, categorical values that are really

  • outside the domain of that category,

  • things like that, problems in your data.

  • Transform is where we do feature engineering.

  • And Transform is one of the more complex components.

  • As you can see from the code there,

  • that could be arbitrarily complex

  • because, depending on the needs of your data

  • set and your model, you may have a lot of feature engineering

  • that you need to do, or you may just have a little bit.

  • The configuration for it is fairly standard.

  • Just one line of code there with some configuration parameters.

  • But it has a key advantage in that it's

  • going to take your feature engineering

  • and it's going to convert it into a TensorFlow graph.

  • That graph then gets prepended to the model

  • that you're training as the input stage to your model.

  • And what that does is it means you're doing the same feature

  • engineering with the same code exactly the same way,

  • both in training and in production

  • when you deploy to any of the deployment targets.

  • So that eliminates the possibility

  • that you may have run into where you

  • have two different environments, maybe even

  • two different languages and you're

  • trying to do the same thing in both places

  • and you hope it's correct.

  • This eliminates that.

  • We call it training serving skew.

  • It eliminates that possibility.

  • Trainer.

  • Well, now we're coming back to the start.

  • Trainer does what we started with.

  • It's going to train a model for us.

  • So this is TensorFlow.

  • And the result is going to be a SavedModel,

  • and a little variant of the SavedModel, the eval SaveModel

  • that we're going to use.

  • It has a little extra information that we're

  • going to use for evaluation.

  • So Trainer has the typical kinds of configuration

  • that you might expect, things like the number of steps,

  • whether or not to use warm-starting.

  • And you can use TensorBoard, including

  • comparing execution runs between the model that you just trained

  • and models that you've trained in the past at some time.

  • So TensorBoard has a lot of very powerful tools

  • to help you understand your training process

  • and the performance of your model.

  • So here's an example where we're comparing

  • two different execution runs.

  • Evaluator uses TensorFlow Model Analysis, one of the libraries

  • that we talked about at the beginning,

  • to do some deep analysis of the performance of your data.

  • So it's not just looking at the top level metrics,

  • like what is the RMSE or the AUC for my whole data set.

  • It's looking at individual slices of your data set

  • and slices of the features within your data set

  • to really dive in at a deeper level

  • and understand the performance.

  • So that things like fairness become

  • very manageable by doing that.

  • If you don't do that sort of analysis,

  • you can easily have gaps that may

  • be catastrophic in the performance of your model.

  • So this becomes a very powerful tool.

  • And there's some visualization tools

  • that we'll look at as well that help you do that.

  • ModelValidator asks that question

  • that I talked about a little while

  • ago where you have a model that's in production,

  • you have this new model that you just trained.

  • Is it better or worse than what I already have?

  • Should I push this thing to production?

  • And if you decide that you're going to push it to production,

  • then Pusher does that push.

  • Now production could be a number of. different things.

  • You could be pushing it to a serving cluster using

  • TensorFlow Serving.

  • You could be pushing it to a mobile application using

  • TensorFlow Lite.

  • You could be pushing it to a web application or a Node.js

  • application using TensorFlow.js.

  • Or you could even just be taking that model

  • and pushing it into a repo with TensorFlow Hub

  • that you might use later for transfer learning.

  • So there's a number of different deployment targets.

  • And you can do all the above with Pusher.

  • Bulk infer is that component that we

  • talked about a little while ago where

  • we're able to take bulk inference requests

  • and run inference across them, and do that in a managed

  • way that allows us to take that result and move it off.

  • All right, orchestrating.

  • We have a number of tasks in our pipeline.

  • How do we orchestrate them?

  • Well, there's different ways to approach it.

  • You can do task-aware pipelines where you simply run a task,

  • you wait for it to finish, and you run the next task.

  • And that's fine.

  • That works.

  • But it doesn't have a lot of the advantages

  • that you can have with a task or data-aware pipeline.

  • This is where we get our metadata.

  • So by setting up the dependencies

  • between our components and our metadata artifacts

  • in a task and data-aware pipeline,

  • we're able to take advantage of a lot of the information

  • over the lifetime of that product or service

  • that that ML deployment that we have in the artifacts

  • that we've produced.

  • Orchestration is done through an orchestrator.

  • And the question is, which orchestrator

  • do you have to use.

  • Well, the answer is you can use whatever you want to use.

  • We have three orchestrators that are supported out of the box--

  • Apache Airflow, Kubeflow, for a Kubernetes

  • containerized environment, and Apache Beam.

  • Those three are not your only selections.

  • You can extend that to add your own orchestration.

  • But in the end, you're going to end up

  • with essentially the same thing, regardless

  • of which orchestrator you're going to use.

  • You're going to end up with a Direct Acyclic Graph, or DAG,

  • that expresses the dependencies between your components, which

  • are really a result of the artifacts that are produced

  • by your components.

  • So here's three examples.

  • They look different, but actually if you look at them,

  • they are the same DAG.

  • We get this question a lot, so I want to address this.

  • What's this cube thing and this TFX thing,

  • and what's the difference between the two?

  • The answer is Kubeflow is really focused on a Kubernetes

  • containerized environment.

  • And it's a great deployment platform

  • for running in a very scalable manageable way.

  • Kubernetes pipelines uses TFX.

  • So you're essentially deploying TFX in a pipeline

  • environment on Kubernetes.

  • And that's Kubeflow pipeline.

  • But TFX can be deployed in other ways as well.

  • So if you don't want to use Kubeflow pipelines,

  • if you want to deploy in a different environment, maybe

  • on-prem in your own data center or what have you,

  • you can use TFX in other environments as well.

  • One of the things that we do, because we're

  • working with large data sets, and there's

  • a lot of processing involved, some

  • of these operations that we're going

  • to do require a lot of processing,

  • we need to distribute that processing over a pipeline.

  • So how do we do that?

  • Well, a component that uses a pipeline

  • is going to create a pipeline for the operations

  • that it wants to do.

  • It's going to hand that pipeline off to a cluster.

  • Could be a Spark cluster, could be a Flink cluster,

  • could be Cloud Dataflow.

  • Map reduce happens on the cluster.

  • And it comes back with a result. But we

  • want to support more than just one or two types of distributed

  • pipelines.

  • So we're working with Apache Beam

  • to add an abstraction from the native layer of those pipelines

  • so that you can take the same code

  • and run it actually on different pipelines

  • without changing your code.

  • And that's what Apache Beam is.

  • There's different runners for different things

  • like Flink and Spark.

  • There's also a really nice one for development

  • called the direct runner or local runner that allow you

  • to run even just on a laptop.

  • But here's the vision for Beam.

  • There's a whole set of pipelines out there that are available.

  • They have strengths and weaknesses.

  • And in a lot of cases, you will already

  • have one that you've stood up and you

  • want to try to leverage that resource.

  • So by supporting all of them, you're

  • able to do this installation.

  • You don't have to spin up a completely different cluster

  • to do that.

  • You can leverage the ones or just expand the ones

  • that you already have.

  • So Beam allows you to do that, and also

  • with different languages.

  • Now in this case, we're only using Python.

  • But Beam as a vision, as an Apache project,

  • allows you to work with other languages

  • as well through different STKs.

  • And now I'd like to introduce Charles Chen, who's

  • going to give us a demo of TFX running

  • on actually just a laptop system in the cloud here.

  • So you'll get to see some live code.

  • CHARLES CHEN: Thank you, Robert.

  • So now that we've gone into detail about TFX and TFX

  • components, I'd like to take the chance

  • to make this really concrete with a live demo

  • of a complete TFX pipeline.

  • So this demo uses the new experimental TFX notebook

  • integration.

  • And the goal of this integration is

  • to make it easy to interactively build up

  • TFX pipelines in a Jupyter or Google Colab notebook

  • environment.

  • So you can try your pipeline out before you export the code

  • and deploy it into production.

  • You can follow along and run this yourself

  • in the Google Colab notebook at this link here.

  • So for the interactive notebook, we introduced one new concept.

  • This is the interactive context.

  • In a production environment, like Robert said,

  • we would construct a complete graph of pipeline components

  • and orchestrated on an engine like Airflow or Kubeflow.

  • By contrast, when you're experimenting in a notebook,

  • you want to interactively execute and see results

  • for individual components.

  • We construct an interactive context

  • which can do two things.

  • The first thing is it can run the component we define.

  • This as context.run.

  • And the second is it can show a visualization of the components

  • output.

  • This is context.show.

  • Let's get started.

  • Here's the overview we've seen of a canonical TFX

  • pipeline where we go from data ingestion to data

  • validation, feature engineering, model training and model

  • validation to deployment.

  • We'll go through each of these in the notebook.

  • Here's the notebook here.

  • And the first thing we do is a bit of setup.

  • This is the PIP install step.

  • And basically, we run the PIP Install

  • to install the Python package and all its dependencies.

  • And if you're following along, after doing the installation,

  • you need to restart the runtime so that the notebook picks up

  • some of the new versions of dependencies.

  • Next, we do some imports, set up some paths, download the data.

  • And finally, we create the interactive context.

  • Once we've done this, we get to our first component,

  • which is ExampleGen, which ingests data into the pipeline.

  • Again, this is just a couple of lines of code.

  • And we run this with context.run.

  • After we're done, we're ready to use

  • the data, which has been ingested and processed

  • into splits.

  • We take the output of ExampleGen and use

  • this in our next component, StatisticsGen,

  • which analyzes data and outputs detailed statistics.

  • This component can also be used standalone outside of a TFX

  • pipeline with the TensorFlow data validation package.

  • You can see that our input here is the output of ExampleGen

  • again.

  • And after we're done, we can visualize

  • this with context.show.

  • For each split, we get a detailed summary statistics

  • and a visualization of our data, which

  • we can dig into to ensure data quality,

  • even before we train a model.

  • After that, we can use SchemaGen to infer a suggested

  • schema for your data.

  • We see that visualized here.

  • This includes the type and domain

  • for each feature in your data set.

  • For example, for categorical features,

  • the domain is inferred to be all the values we've seen so far.

  • This is just the starting point.

  • And you can then edit and curate the schema

  • based on your domain knowledge.

  • Once we have the schema, we can use the ExampleValidator

  • to perform anomaly detection.

  • That is, find items in your input data

  • that don't match your expected schema.

  • This is especially useful as your pipeline evolves over time

  • with new data sets coming in.

  • We visualize this.

  • And any unexpected values are highlighted.

  • If you see anomalies, you might want

  • to either update your schema or fix your data collection

  • process.

  • After our data is validated, we move onto data transformation

  • or feature engineering.

  • This is done in the Transform component.

  • The first thing we do is write a little common code

  • and pre-processing function with TensorFlow Transform.

  • You can look at this code in more detail on your own.

  • It defines the transformations we

  • do using TensorFlow Transform.

  • And this means for each feature of your data,

  • we define the individual transformations.

  • This comes together in the Transform component

  • where feature engineering is performed.

  • And we output the transform graph and the engineered

  • features.

  • This will take a bit of time to run.

  • And after that's done, we get to the heart

  • of the model with the trainer.

  • Here, we define a training function that

  • returns a TensorFlow estimator.

  • We build the estimator and return this function

  • from the function.

  • And this is just TensorFlow.

  • So once we have this, we run the Trainer component,

  • which is going to produce a trained model for evaluation

  • and serving.

  • You can watch it train here.

  • It'll give you the loss, evaluate, and then produce

  • a SavedModel for evaluation and serving.

  • After we've trained the model, we

  • have the Evaluator component.

  • This uses the standalone TensorFlow Model Analysis

  • library.

  • In addition to overall metrics over the entire data set,

  • we can define more granular feature column

  • slices for evaluation.

  • The Evaluator component then computes

  • metrics for each data slice, which

  • you can then visualize with interactive visualizations.

  • What makes TensorFlow Model Analysis really powerful

  • is that in addition to the overall metrics we see here,

  • we can analyze model performance on granular feature slices--

  • granular feature column slices, that is.

  • So here we see the metrics rendered

  • across one slice of our data.

  • And we can do even more granular things

  • with multiple columns of our data.

  • After we've evaluated our model, we come to the ModelValidator.

  • Based on a comparison of the performance

  • of your model compared to an existing baseline model,

  • this component checks for whether or not

  • the model is ready to push to production.

  • Right now, since we don't have any existing models,

  • this check will by default return true.

  • You can also customize this check

  • by extending the ModelValidator executor.

  • The output of this check is then used in the next component,

  • the Pusher.

  • The Pusher pushes your model, again,

  • to a specific destination for production.

  • This can be TensorFlow Serving, a file system destination

  • or a cloud service like Google Cloud Platform.

  • Here, we configure the Pusher to write the model

  • to a file system directory.

  • Once we've done this, we've now architected a complete TFX

  • pipeline.

  • With minimal modifications, you can use your new pipeline

  • in production in something like Airflow or Kubeflow.

  • And essentially, this would be getting

  • rid of your usage of the interactive context

  • and creating a new pipeline object to run.

  • For convenience, we've included a pipeline export feature

  • in the notebook that tries to do this for you.

  • So here, well, first we do some housekeeping--

  • we mount Google Drive.

  • We select a runner type.

  • Let's say I want to run this on Airflow.

  • We set up some paths.

  • We specify the components of the exported pipeline.

  • We do the pipeline export.

  • And finally, we use this export cell

  • to get a zip archive of all you need

  • to run the pipeline on an engine like Airflow.

  • With that, I'll hand it back to Robert,

  • who will talk about how to extend TFX for your own needs.

  • ROBERT CROWE: Thanks, Charles.

  • All right, so that was the notebook.

  • Let me just advance here.

  • All right, custom components.

  • So again, these are the standard components

  • that come out of the box.

  • With TFX, but you are not limited to those.

  • You can write your own custom components.

  • So let's talk about how to do that.

  • First of all, you can do a semi-custom component

  • by taking an existing component and working

  • with the same inputs, the same outputs, essentially

  • the same contract, but replacing the executor by just overriding

  • the existing executor.

  • And that executor, remember, is where the work is done.

  • So changing that executor is going

  • to change that component in a very fundamental way.

  • So if you're going to do that, you're

  • going to extend the base executor

  • and implement a do function.

  • And that's what the code looks like.

  • There's a custom config dictionary

  • that allows you to pass additional things

  • into your component.

  • So this is a fairly easy and powerful way

  • to create your own custom component.

  • But you can also, if you want--

  • and this is how you would fit a custom component

  • into an existing pipeline-- it just fits in

  • like any other component.

  • You can also, though, do a fully custom component

  • where you have a different component

  • spec, a different contract, different inputs,

  • different outputs, that don't exist in an existing component.

  • And those are defined in the component spec that gives you

  • the parameters and the inputs and the outputs

  • to your component.

  • And then you are going to need an executor for that

  • as well, just like you did before.

  • But it takes you even further.

  • So your executor, your inputs, your outputs, that's

  • a fully custom component.

  • Now I've only got three minutes left.

  • I'm going to go through a quick example of really trying

  • to understand why model understanding and model

  • performance are very important.

  • First of all, I've talked about data

  • lifecycle a couple of times, trying to understand

  • how things change over time.

  • The ground truth may change.

  • Your data characteristics, the distribution

  • of each of your features may change.

  • Conditions in the world may change.

  • You may have different competitors.

  • You may expand into different markets, different geographies.

  • Styles may change.

  • The world changes.

  • Over the life of your deployment,

  • that becomes very important.

  • So in this example, and this is a hypothetical example,

  • this company is an online retailer who is selling shoes.

  • And they're trying to use click-through rates

  • to decide how much inventory they should order.

  • And they discover that suddenly--

  • they've been going along and now on a particular slice

  • of their data--

  • not their whole data set, just a slice of it--

  • things have really gone south.

  • So they've got a problem.

  • What do they do?

  • Well, first of all, it's important to understand

  • the realities around this.

  • Mispredictions do not have uniform cost.

  • Across your business or whatever service you're providing,

  • different parts of that will have different costs.

  • The data you have is never the data that you wish you had.

  • And the model, as in this case, the model objective

  • is often a proxy for what you really want to know.

  • So they're trying to use click-through rates as a proxy

  • for ordering inventory.

  • But the last one, the real world doesn't stand still,

  • is the key here.

  • You need to really understand that

  • when you go into a production environment.

  • So what can they do?

  • Well, their problems are not with the data set that they

  • use to train their model.

  • Their problems are with the current inference requests

  • that they're getting.

  • And there's a difference between those two.

  • So how do they deal with that?

  • Well, they're going to need labels.

  • Assuming they're doing supervised learning,

  • they're going to need to label those inference requests

  • somehow.

  • How can they do that?

  • If they're in the fortunate position

  • of being able to get direct feedback,

  • they can use their existing processes to label that data.

  • So for example, if they're trying

  • to predict the click-through rate

  • and they have click-through rate data that they're collecting,

  • they can use that directly.

  • That's great.

  • Many people are not in that situation.

  • So you see a lot of environments where

  • you're trying to use things like semi-supervision and humans

  • to label the data that you have where

  • a subset of the data that you have so you can try

  • to understand how things have changed since you

  • trained your model.

  • Weak supervision is a very powerful tool as well.

  • But it's not that easy to use in a lot of cases.

  • You need to try to apply historical data or other types

  • of modeling, heuristics.

  • And in many cases, those are giving you a labeling signal

  • that is not 100% accurate.

  • But it gives you some direction and you can work.

  • There are modeling techniques to work

  • with that kind of a signal.

  • TensorFlow Model Analysis.

  • The Fairness indicators that you may have seen today--

  • and we're out on the show floor with--

  • those are great tools to try to understand this and identify

  • the slices and the problems that you have with your data.

  • But first things first, you need to check your data,

  • look for outliers, check your feature space coverage.

  • How well does your data cover the feature space

  • that you have?

  • And use the tools that we give you

  • in TensorFlow Data Validation and TensorFlow Model Analysis.

  • We also have the what-if tool, a very powerful tool

  • for doing exploration of your data and your model.

  • And in the end, you need to quantify the cost because you

  • are never going to get 100%.

  • So how much is that extra 5% worth?

  • In a business environment, you need to understand that.

  • And that's TFX.

  • TFX is, again, what Google built because we needed it.

  • And now, we want you to have it too.

  • So it's available is an open source platform that we

  • encourage you all to build on.

  • And since it's open source, we hope

  • you're going to help us contribute and build

  • the platform to make it better in the future as well.

  • So on behalf of myself and my colleague

  • Charles, thanks very much.

  • [APPLAUSE]

ROBERT CROWE: I'm Robert Crowe.

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TFX:使用TensorFlow生產ML管道(TF World '19) (TFX: Production ML pipelines with TensorFlow (TF World '19))

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    林宜悉 發佈於 2021 年 01 月 14 日
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