diff options
Diffstat (limited to 'includes/rts/storage/GC.h')
| -rw-r--r-- | includes/rts/storage/GC.h | 40 |
1 files changed, 17 insertions, 23 deletions
diff --git a/includes/rts/storage/GC.h b/includes/rts/storage/GC.h index 04548be379..4aa44bd344 100644 --- a/includes/rts/storage/GC.h +++ b/includes/rts/storage/GC.h @@ -15,41 +15,35 @@ /* ----------------------------------------------------------------------------- * Generational GC * - * We support an arbitrary number of generations, with an arbitrary number - * of steps per generation. Notes (in no particular order): + * We support an arbitrary number of generations. Notes (in no particular + * order): * - * - all generations except the oldest should have the same - * number of steps. Multiple steps gives objects a decent - * chance to age before being promoted, and helps ensure that - * we don't end up with too many thunks being updated in older - * generations. + * - Objects "age" in the nursery for one GC cycle before being promoted + * to the next generation. There is no aging in other generations. * - * - the oldest generation has one step. There's no point in aging - * objects in the oldest generation. - * - * - generation 0, step 0 (G0S0) is the allocation area. It is given + * - generation 0 is the allocation area. It is given * a fixed set of blocks during initialisation, and these blocks * normally stay in G0S0. In parallel execution, each * Capability has its own nursery. * - * - during garbage collection, each step which is an evacuation - * destination (i.e. all steps except G0S0) is allocated a to-space. - * evacuated objects are allocated into the step's to-space until - * GC is finished, when the original step's contents may be freed - * and replaced by the to-space. + * - during garbage collection, each generation which is an + * evacuation destination (i.e. all generations except G0) is + * allocated a to-space. evacuated objects are allocated into + * the generation's to-space until GC is finished, when the + * original generations's contents may be freed and replaced + * by the to-space. * - * - the mutable-list is per-generation (not per-step). G0 doesn't - * have one (since every garbage collection collects at least G0). + * - the mutable-list is per-generation. G0 doesn't have one + * (since every garbage collection collects at least G0). * - * - block descriptors contain pointers to both the step and the - * generation that the block belongs to, for convenience. + * - block descriptors contain a pointer to the generation that + * the block belongs to, for convenience. * * - static objects are stored in per-generation lists. See GC.c for * details of how we collect CAFs in the generational scheme. * - * - large objects are per-step, and are promoted in the same way - * as small objects, except that we may allocate large objects into - * generation 1 initially. + * - large objects are per-generation, and are promoted in the + * same way as small objects. * * ------------------------------------------------------------------------- */ |