Alpaka algorithms and modules in CMSSW

Introduction

Compilation model

Overall guidelines

Data formats

Implicit data transfers

Data copy definitions

Data products with `memcpy()`ed pointers

EDProducer

ESProducer

`PortableCollection`

Modules

Base classes

Event, EventSetup, Records

Tokens

`fillDescriptions()`

Copy e.g. configuration data to all devices in EDProducer

Guarantees

Examples

EDProducer

ESProducer to reformat an existing ESProduct for use in device

ESProducer to derive a new ESProduct from an existing device-side ESProduct

Configuration

Explicit module type (non-portable)

Module type resolver (portable)

Examples on explicitly setting the backend

For individual modules

For all Alpaka modules

For entire job (i.e. also for non-Alpaka modules)

Blocking synchronization (for testing)

Unit tests