I'm running massive parallel jobs on Azure Batch now, works ok but to my regret I can't seem to use A0 instances. The jobs I run are very low in memory or disk usage, so I only want 'bare' cores ideally.
A1 instances are fine also, but the cost ~ 5 ct/hr while A0's cost ~1,5 ct/hr, and they would be enough.
So: how can I use A0's in Azure batch, and if not, I guess it would be (a lot) cheaper to run on Worker roles?
Azure Batch supports all Azure VM sizes except STANDARD_A0 and those with premium storage (STANDARD_GS, STANDARD_DS, and STANDARD_DSV2 series).
see https://azure.microsoft.com/en-us/documentation/articles/batch-api-basics/ for more information.
The workerroles can indeed provide the most economical solution.