Sean T Allen

www.seantallen.com

• Engineer @ Antithesis
• Member of the Pony core team
• Message Passing Devotee
• Ricky Bobby Apostle

GC Made Fast

Most Engineers I Know

Message Passing
scales better than
Shared State

Coordination
Kills
Performance

Act Locally

Gossip Globally

The Coordination Tax

Atomic reference counting

Lock-free reclamation

Cache-line bouncing

Didn't Rust Solve This?

Single thread? Yes

Multiple threads? No

Stop the World GC

Maximalist Coordination

Pony's Actors

No shared mutable state

No copying to share data

Reference Capabilities

Mutable or immutable

Shareable or unique

Compile time, not runtime

Per-Actor Heaps

Message Passing
Is Cheap

Gossip

Coordination Is Slow, GC Isn't

Go All In

Coordination Reducing Design