AzureML Compute Instance Mount Data (SDK V2)

Summary

The AzureML Compute Instance provides a managed environment for machine learning workflows, and accessing blob data storage is a common requirement. In this scenario, the goal is to mount the blob data storage and access the data as if it were a native file system, without downloading the data to disk. The AzureML V2 SDK is being used, and Identity-based access is enabled, with shared access keys disabled.

Root Cause

The root cause of the issue is the lack of a straightforward method to mount Azure Blob Storage in an AzureML Compute Instance using the AzureML V2 SDK. The current implementation requires a workaround using BlobClient and io streaming. The key causes are:

  • Limited support for mounting blob storage in AzureML Compute Instances
  • Restrictions imposed by Identity-based access and disabled shared access keys
  • Lack of a simple, native file system-like interface for blob storage access

Why This Happens in Real Systems

This issue occurs in real systems due to the following reasons:

  • Security constraints: Identity-based access and disabled shared access keys are security best practices, but they can limit the availability of certain features
  • Complexity of cloud storage: Cloud storage systems like Azure Blob Storage have different access patterns and authentication mechanisms compared to traditional file systems
  • Evolution of SDKs: The AzureML V2 SDK is a relatively new release, and some features may not be fully developed or documented

Real-World Impact

The real-world impact of this issue includes:

  • Inefficient data access: Downloading data to disk can be slow and inefficient, especially for large datasets
  • Increased storage costs: Storing data locally on the Compute Instance can incur additional storage costs
  • Complexity in workflow implementation: The workaround using BlobClient and io streaming can add complexity to machine learning workflows

Example or Code (if necessary and relevant)

from azure.storage.blob import BlobServiceClient
from azure.core.credentials import DefaultAzureCredential

# Create a BlobServiceClient object
blob_service_client = BlobServiceClient(
    account_url="https://.blob.core.windows.net",
    credential=DefaultAzureCredential()
)

# Get a reference to a container
container_client = blob_service_client.get_container_client("")

# Get a reference to a blob
blob_client = container_client.get_blob_client("")

# Download the blob content
blob_data = blob_client.download_blob().content_as_bytes()

How Senior Engineers Fix It

Senior engineers can fix this issue by:

  • Using the AzureML V2 SDK’s built-in support for Azure Blob Storage: Although limited, the SDK provides some functionality for working with blob storage
  • Implementing a custom mounting solution: Using libraries like blobfuse or azure-storage-fuse to mount the blob storage as a file system
  • Optimizing the workflow implementation: Minimizing the amount of data that needs to be downloaded or stored locally

Why Juniors Miss It

Junior engineers may miss this issue due to:

  • Lack of experience with cloud storage systems: Limited familiarity with the nuances of cloud storage and its access patterns
  • Insufficient understanding of Identity-based access: Not fully grasping the implications of Identity-based access and disabled shared access keys
  • Overreliance on SDK documentation: Not exploring alternative solutions or workarounds when the SDK documentation appears to be limited or unclear