How can we add complex preprocessing in AWS Sagemaker inference - amazon-web-services

I am using AWS Sagemaker to deploy my speech models trained outside of Sagemaker. I am able to convert my model into something Sagemaker would understand and have deployed it as an endpoint. Problem is that Sagemaker directly loads the model and calls .predict to get the inference. I am unable to figure out where can I add my preprocessing functions in the deployed model. It is suggested to use AWS Lambda or another server for preprocessing. Is there any way I can incorporate complex preprocessing (cannot be done by simple Scikit, Pandas like framework) in Sagemaker itself?

You will want to adjust the predictor.py file in the container that you are bringing your speech models in. Assuming you are using Bring Your Container to deploy these models on SageMaker you will want to adjust the predictor code to include the preprocessing functionality that you are working with. For any extra dependencies that you are working with make sure to update this in your Dockerfile that you are bringing. Having the preprocessing functionality within the predictor file will make sure your data is transformed, processed as you desire before returning predictions. This will add to the response time however, so if you have heavy preprocessing workloads or ETL that needs to occur you may want to look into a service as AWS Glue (ETL) or Kinesis (real-time data streaming/data transformation). If you choose to use Lambda you want to keep in mind the 15 minute timeout limit.
I work for AWS & my opinions are my own

Related

AWS Sagemaker - Custom Training Job not saving Model output

I'm running a training job using AWS SageMaker and i'm using a custom Estimator based on an available docker image from AWS. I wanted to get some feedback on whether my process is correct or not prior to deployment.
I'm running the training job in a docker container using 'local' in a SageMaker notebook instance and the training job runs successfully. However, after the job completes and saves the model to opt/model/models within the docker image, once the docker container exits, the model saved from training is lost. Ideally, i'd like to use the model for inference, however, I'm not sure about the best way of doing it. I have also tried the training job after pushing the image to ECR, but the same thing happens.
It is my understanding that the docker state is lost, once the image exits, as such, is it possible to persist the model that was produced in training in the image? One option I have thought about is saving the model output to an S3 bucket once the training job is complete, then pulling that model into another docker image for inference. Is this expected behaviour and the correct way of doing it?
I am fairly new to using SageMaker but i'd like to do it according to best practices. I've looked at a lot of the AWS documents and followed the tutorials but it doesn't seem to mention explicitly if this is how it should be done.
Thanks for any feedback on this.
You can refer to Rok's comment on saving a model file when you're using a custom estimator. That said, SageMaker built-in estimators save the model artifacts to S3. To make inferences using that model, you can either use a real-time inference endpoint for real time predictions, or a batch transformer to run inferences in batch mode. In both cases, you'll have to point the configuration to the container for inference and the model artifacts. the amazon-sagemaker-examples repository has examples for common frameworks, especially, the scikit-learn example has detailed explanations.
Also, make sure the model is being saved to /opt/ml/model/, not opt/model/models as mentioned in your question.

Multimodel Inference AWS Sagemaker with preprocessing

I have a usecase for hosting multiple xgboost models in one sagemaker endpoint. The models have a slightly different feature set and preprocessing for features.
The two options I am considering are:
Creating models with custom docker images and hosting them in one endpoint using production variants. I will then invoke the endpoint with the variant name and correct feature set.
Sagemaker Inference Toolkit (multi-model-server). In the handler script I am planning to pre-process the input differently based on the model name.
Are these the right approach for the problem? Or is there a better approach for working with Sagemaker and multiple xgboost model with pre and post processing?

Calling SageMaker Notebook instance function by endpoint

I am a newbie in AWS. Right now I have defined an image segmentation function in SageMaker notebook instance and this will return masks.
I didn't train my models there, what I have done is pip install models packages there, upload pre-trained weights manually. The rest is very similar to working in local machine: I imported package, load the weights, defined a function to take an image as input then outputs masks.
My question is: is there a way to host my function so that I can call it with URL endpoint + one image info, then it returns me masks in response?
Again I am so new to AWS and I begin to doubt SageMaker is not designed for this job... The reason I chose SageMaker is the need of computing capacity, I don't think I can do this job with pure lambda.
SageMaker inference endpoints currently rely on an interface based on Docker images. At the base level, you can set up a Docker image that runs a web server and responds to the endpoints on the ports that AWS require. This guide will show you how to do it: https://docs.aws.amazon.com/sagemaker/latest/dg/your-algorithms-inference-code.html.
This is an annoying amount of work. If you're using a well-known framework they have a container library that contains some boilerplate code you might be able to reuse: https://github.com/aws/sagemaker-containers. You might have to do some customization there.
Or don't use SageMaker inference endpoints at all :) If your model can fit within the size / memory restrictions of AWS Lambda, that is an easier option!
Full disclaimer, I'm working on a platform that competes with SageMaker: Model Zoo

how to run a pre-trained model in AWS sagemaker?

I have a model.pkl file which is pre-trained and all other files related to the ml model. I want it to deploy it on the aws sagemaker.
But without training, how to deploy it to the aws sagmekaer, as fit() method in aws sagemaker run the train command and push the model.tar.gz to the s3 location and when deploy method is used it uses the same s3 location to deploy the model, we don't manual create the same location in s3 as it is created by the aws model and name it given by using some timestamp. How to put out our own personalized model.tar.gz file in the s3 location and call the deploy() function by using the same s3 location.
All you need is:
to have your model in an arbitrary S3 location in a model.tar.gz archive
to have an inference script in a SageMaker-compatible docker image that is able to read your model.pkl, serve it and handle inferences.
to create an endpoint associating your artifact to your inference code
When you ask for an endpoint deployment, SageMaker will take care of downloading your model.tar.gz and uncompressing to the appropriate location in the docker image of the server, which is /opt/ml/model
Depending on the framework you use, you may use either a pre-existing docker image (available for Scikit-learn, TensorFlow, PyTorch, MXNet) or you may need to create your own.
Regarding custom image creation, see here the specification and here two examples of custom containers for R and sklearn (the sklearn one is less relevant now that there is a pre-built docker image along with a sagemaker sklearn SDK)
Regarding leveraging existing containers for Sklearn, PyTorch, MXNet, TF, check this example: Random Forest in SageMaker Sklearn container. In this example, nothing prevents you from deploying a model that was trained elsewhere. Note that with a train/deploy environment mismatch you may run in errors due to some software version difference though.
Regarding your following experience:
when deploy method is used it uses the same s3 location to deploy the
model, we don't manual create the same location in s3 as it is created
by the aws model and name it given by using some timestamp
I agree that sometimes the demos that use the SageMaker Python SDK (one of the many available SDKs for SageMaker) may be misleading, in the sense that they often leverage the fact that an Estimator that has just been trained can be deployed (Estimator.deploy(..)) in the same session, without having to instantiate the intermediary model concept that maps inference code to model artifact. This design is presumably done on behalf of code compacity, but in real life, training and deployment of a given model may well be done from different scripts running in different systems. It's perfectly possible to deploy a model with training it previously in the same session, you need to instantiate a sagemaker.model.Model object and then deploy it.

Re-hosting a trained model on AWS SageMaker

I have started exploring AWS SageMaker starting with these examples provided by AWS. I then made some modifications to this particular setup so that it uses the data from my use case for training.
Now, as I continue to work on this model and tuning, after I delete the inference endpoint once, I would like to be able to recreate the same endpoint -- even after stopping and restarting the notebook instance (so the notebook / kernel session is no longer valid) -- using the already trained model artifacts that gets uploaded to S3 under /output folder.
Now I cannot simply jump directly to this line of code:
bt_endpoint = bt_model.deploy(initial_instance_count = 1,instance_type = 'ml.m4.xlarge')
I did some searching -- including amazon's own example of hosting pre-trained models, but I am a little lost. I would appreciate any guidance, examples, or documentation that I could emulate and adapt to my case.
Your comment is correct - you can re-create an Endpoint given an existing EndpointConfiguration. This can be done via the console, the AWS CLI, or the SageMaker boto client.
https://docs.aws.amazon.com/cli/latest/reference/sagemaker/create-endpoint.html
https://boto3.amazonaws.com/v1/documentation/api/latest/reference/services/sagemaker.html#SageMaker.Client.create_endpoint