Introduction

Von Neumann Bottleneck

• The von Neumann architecture is a hardware architecture.
• The von Neumann architecture uses a single bus for both, code and data.
• This architecture gives rise to something called the von Neumann Bottleneck.
• The problem is that code cannot execute while data is being transferred.
• Other hardware architectures repair this problem by using multiple buses.  
• Other architectures allow asynchronous (at the same time) transfer of data and code.

                                                                                                    

Can Programming Be Liberated...

• famous paper "Can programming be liberated from the von Neumann style?: a functional style and its algebra of programs"^[1] 
• proposes the idea that the von Neumann hardware architecture translates directly into the software domain

                                                                                                    

ALGOL Bottleneck

• Software has yet another bottleneck that is orthogonal to the underlying hardware
• I call this the ALGOL Bottleneck
• Lack of asynchrony

                                                                                                    

Fiction vs. Reality

Fiction: Libraries are Independent

How Programmers Think About Libraries

                                                                                                    

Reality: Libraries Share A Global Variable

How Libraries Actually Work

The stack is a data structure.

The stack is a global variable.

The stack is shared by all functions.

The stack records dynamic call history.

The stack is a dynamic dependency chain between functions.

                                                                                                    

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[1] https://dl.acm.org/doi/10.1145/359576.359579