This repository is for development of Whippet, a new garbage collector implementation, eventually for use in Guile Scheme.
Whippet is an embed-only C library, designed to be copied into a program's source tree. It exposes an abstract C API for managed memory allocation, and provides a number of implementations of that API.
See the documentation.
- api/: The user-facing API. Also, the "embedder API"; see the manual for more.
- doc/: Documentation, such as it is.
- src/: The actual GC implementation. The specific
implementations of the Whippet API are
semi.c
, a semi-space collector;bdw.c
, the third-party BDW-GC conservative parallel stop-the-world mark-sweep segregated-fits collector with lazy sweeping; andwhippet.c
, the whippet collector. - benchmarks/: Benchmarks. A work in progress.
- test/: A dusty attic of minimal testing.
- Pinning
- Conservative stacks
- Conservative data segments
- Heap growth/shrinking
- Debugging/tracing
- Finalizers
- Weak references / weak maps
- Immix-style opportunistic evacuation
[ ] Overflow allocation(should just evacuate instead)- Generational GC via sticky mark bits
- Generational GC with semi-space nursery
- Concurrent marking with SATB barrier
It sounds better than WIP (work-in-progress) garbage collector, doesn't it? Also apparently a whippet is a kind of dog that is fast for its size. It would be nice if whippet-gc turns out to have this property.
Copyright (c) 2022-2023 Andy Wingo
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Note that some benchmarks have other licenses; see
benchmarks/README.md
for more.