Dive into `Gaudi`

Author:

yong

0.1 Plugin Service and Factory 

0.2 Value Semantics and Ownership Management 

Basically, it’s like shared pointer implementation to manage the underlying resources.

0.2.1 idoms 

0.2.1.1 copy-swap and copy-elison 

For copy assignment, copy-swap avoids the self-assignment bug and provides better exception safety. copy-elison (i.e. pass-by-value style assignment in this case) further improves the performances in cases where rvalue on the right side.

See:

More C++ Idioms wikibook
podio ObjBase implementation
boost shared_ptr implementation

0.2.1.2 reference-counting 

See:

The example is almost the same as podio’s data model implementation

0.2.1.3 handle-body (AKA: pointer to implementation)

See the previous section’s link.

0.3 Parallelism 

0.3.1 Multi-Process 

0.3.2 Multi-Thread 

0.3.3 Multi-Job 

0.3.4 Multi-Node??

0.4 Finite State Machine (FSM)

0.5 Curiously Recurring Template Pattern (CRTP)

1.1 Concurrency 

1.1.1 GaudiHive (MT)

1.1.2 GaudiMP (MP)

1.2 Interface 

1.2.1 IService 

1.2.2 IProperty 

1.2.3 ITool 

1.2.4 IStateful 

2.1 overview 

Gaudi Evolution for Future Chanllege

Task-based, intra-event parallelization: GaudiHive
Reentrant Algorithm
- A subset: Gaudi::Functional framework

2.2 Config2 

~/src/physics/key4hep/Gaudi/GaudiConfiguration/doc/README.md

2.3 Histogram 

see this commit