https://community.databricks.com/t5/data-engineering/sparksession-getactivesession-is-suddenly-broken-in-python-multi/m-p/176357#M57127 <P>Hello everyone,</P><P>Around 3PM EST yesterday (2026-11-12), dozens of Lakeflow jobs started failing on both classic and serverless compute with distinct symptoms</P><P>1. On classic compute (DBR 15.4), reading a file from S3 would result in a PATH NOT FOUND error</P><P>2. On serverless compute (v2 and v5), reading a file from S3 would result in a "'NoneType' has not attribute 'read'" error indicating the SparkSession object was None/null</P><P>The issue appears to be resolved on classic compute as of 6PM EST 2026-11-12. The issue is ongoing on serverless compute. This is the simplest bit of code that demonstrates the issue.</P><LI-CODE lang="python">from concurrent.futures import ThreadPoolExecutor from pyspark.sql import SparkSession def test(foo): print(SparkSession.getActiveSession()) with ThreadPoolExecutor(max_workers=4) as executor: future_to_batch = { executor.submit(test, foo): foo for foo in [“A”, “B”, “C”, “D”] }</LI-CODE><P>Instead of a SparkSession object appearing in cell output, we see "None". Replacing SparkSession.getActiveSession() with SparkSession.builder.getOrCreate() alleviates the problem.</P><P>Is anyone else seeing this?</P> Fri, 13 Nov 2026 15:45:09 GMT ifishbein 2026-11-13T15:45:09Z https://community.databricks.com/t5/data-engineering/sparksession-getactivesession-is-suddenly-broken-in-python-multi/m-p/176357#M57127 <P>Hello everyone,</P><P>Around 3PM EST yesterday (2026-11-12), dozens of Lakeflow jobs started failing on both classic and serverless compute with distinct symptoms</P><P>1. On classic compute (DBR 15.4), reading a file from S3 would result in a PATH NOT FOUND error</P><P>2. On serverless compute (v2 and v5), reading a file from S3 would result in a "'NoneType' has not attribute 'read'" error indicating the SparkSession object was None/null</P><P>The issue appears to be resolved on classic compute as of 6PM EST 2026-11-12. The issue is ongoing on serverless compute. This is the simplest bit of code that demonstrates the issue.</P><LI-CODE lang="python">from concurrent.futures import ThreadPoolExecutor from pyspark.sql import SparkSession def test(foo): print(SparkSession.getActiveSession()) with ThreadPoolExecutor(max_workers=4) as executor: future_to_batch = { executor.submit(test, foo): foo for foo in [“A”, “B”, “C”, “D”] }</LI-CODE><P>Instead of a SparkSession object appearing in cell output, we see "None". Replacing SparkSession.getActiveSession() with SparkSession.builder.getOrCreate() alleviates the problem.</P><P>Is anyone else seeing this?</P> Fri, 13 Nov 2026 15:45:09 GMT https://community.databricks.com/t5/data-engineering/sparksession-getactivesession-is-suddenly-broken-in-python-multi/m-p/176357#M57127 ifishbein 2026-11-13T15:45:09Z