Feature request: Support WDL 1.2 and/or retry attempt in task

[Ben-Habermeyer]

Hello, I have a feature request for dxCompiler. The purpose is to dynamically choose a larger instance type on a failure such as OOM. An example is that variant calling on a tumor sample with extra high tumor mutation burden can fail, but that is not known at runtime by any metric of the input file contents such as size that could be used dynamically choose an instance with larger memory.

Nextflow and WDL 1.2 appear to have support for "attempt" https://github.com/openwdl/wdl/blob/wdl-1.2/SPEC.md#max_retries https://github.com/openwdl/wdl/blob/wdl-1.2/SPEC.md#runtime-access-to-requirements-hints-and-metadata "attempt: The current task attempt. The value must be 0 the first time the task is executed, and incremented by 1 each time the task is retried (if any)"

The runtime block could then contain something like the following. Part of them motivation is that the larger instance is significantly more expensive and is only needed for some set of samples, which cannot be determined in advance (as the variant calling is what infers tumor mutational burden).

dx_instance_type: if attempt==0 then "mem2_ssd1_gpu_x16" else "mem2_ssd1_gpu_x48"

cc @emiloslavsky

[Ben-Habermeyer]

@emiloslavsky any thoughts on this?