diff options
| author | simonmar <unknown> | 2006-01-17 16:03:47 +0000 |
|---|---|---|
| committer | simonmar <unknown> | 2006-01-17 16:03:47 +0000 |
| commit | da69fa9c5047c5b0d05bdb05eaddefa1eb5d5a36 (patch) | |
| tree | e36c0dbe532aa64733194420ff9b0dd96359e7f6 /ghc/rts/GCCompact.c | |
| parent | ba41623270c1d541e74bd5182e1b4fcbe99809cc (diff) | |
| download | haskell-da69fa9c5047c5b0d05bdb05eaddefa1eb5d5a36.tar.gz | |
[project @ 2006-01-17 16:03:47 by simonmar]
Improve the GC behaviour of IOArrays/STArrays
See Ticket #650
This is a small change to the way mutable arrays interact with the GC,
that can have a dramatic effect on performance, and make tricks with
unsafeThaw/unsafeFreeze redundant. Data.HashTable should be faster
now (I haven't measured it yet).
We now have two mutable array closure types, MUT_ARR_PTRS_CLEAN and
MUT_ARR_PTRS_DIRTY. Both are on the mutable list if the array is in
an old generation. writeArray# sets the type to MUT_ARR_PTRS_DIRTY.
The garbage collector can set the type to MUT_ARR_PTRS_CLEAN if it
finds that no element of the array points into a younger generation
(discovering this required a small addition to evacuate(), but rough
tests indicate that it doesn't measurably affect performance).
NOTE: none of this affects unboxed arrays (IOUArray/STUArray), only
boxed arrays (IOArray/STArray).
We could go further and extend the DIRTY bit to be per-block rather
than for the whole array, but for now this is an easy improvement.
Diffstat (limited to 'ghc/rts/GCCompact.c')
| -rw-r--r-- | ghc/rts/GCCompact.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/ghc/rts/GCCompact.c b/ghc/rts/GCCompact.c index 58753feed4..9d05f5d49a 100644 --- a/ghc/rts/GCCompact.c +++ b/ghc/rts/GCCompact.c @@ -138,7 +138,8 @@ obj_sizeW( StgClosure *p, StgInfoTable *info ) return pap_sizeW((StgPAP *)p); case ARR_WORDS: return arr_words_sizeW((StgArrWords *)p); - case MUT_ARR_PTRS: + case MUT_ARR_PTRS_CLEAN: + case MUT_ARR_PTRS_DIRTY: case MUT_ARR_PTRS_FROZEN: case MUT_ARR_PTRS_FROZEN0: return mut_arr_ptrs_sizeW((StgMutArrPtrs*)p); @@ -478,7 +479,8 @@ update_fwd_large( bdescr *bd ) // nothing to follow continue; - case MUT_ARR_PTRS: + case MUT_ARR_PTRS_CLEAN: + case MUT_ARR_PTRS_DIRTY: case MUT_ARR_PTRS_FROZEN: case MUT_ARR_PTRS_FROZEN0: // follow everything @@ -657,7 +659,8 @@ thread_obj (StgInfoTable *info, StgPtr p) case ARR_WORDS: return p + arr_words_sizeW((StgArrWords *)p); - case MUT_ARR_PTRS: + case MUT_ARR_PTRS_CLEAN: + case MUT_ARR_PTRS_DIRTY: case MUT_ARR_PTRS_FROZEN: case MUT_ARR_PTRS_FROZEN0: // follow everything |