Hi ,
Thanks for reaching out to Microsoft Q&A.
increase pool size (more nodes) + raise max concurrent sessions + keep executor footprint small. That combination will allow 12 to 16 parallel notebooks reliably, depending on workload complexity.
Your current synapse spark pool (Large nodes, 3to 6 autoscale, 16 vCores / 128 GB each) and notebook settings (Small executors, 1 to 2 dynamically allocated) limit concurrency. To run more than 8 notebooks in parallel, optimise as follows:
- Increase node count > move autoscale upper limit to 8–10 nodes.
- Use smaller executors > keep executor size Small (4 vCores, 28 GB) to maximise parallel sessions.
- Lower per notebook resource use > limit each notebook to 1 executor, dynamic allocation enabled.
- Adjust concurrency setting > in synapse Spark pool configuration, raise “Maximum concurrent sessions” (default is 8).
- Avoid cache contention > reduce Intelligent cache below 50 % if memory pressure occurs.
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