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.
With the introduction of Azure Batch Low Priority VMs the prices for certain types of VMs (assuming that your workload is amenable for preemption) are now far lower than either STANDARD_A0 or even a BASIC_A0 instance.
For example: pricing taken on 2017-05-15, a Low Priority STANDARD_A1_V2 instance in West Central US costs $0.007/hr compared to $0.02/hr for a STANDARD_A0. Not only do you get more performance, but you won't be on shared infra like the A0. You can view Batch Low Priority Pricing here.
