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| author | Jason Evans <jasone@canonware.com> | 2015-01-30 22:54:08 -0800 |
|---|---|---|
| committer | Jason Evans <jasone@canonware.com> | 2015-02-04 16:51:53 -0800 |
| commit | 8d0e04d42f4750970ac3052a6c76379b60aba5dc (patch) | |
| tree | 25d71a94a914eb4f69c524f14b5f8d28eaf01881 /include/jemalloc/internal/chunk.h | |
| parent | c810fcea1fa7983ef5bcabe6556cdc19dde6dd8d (diff) | |
| download | jemalloc-8d0e04d42f4750970ac3052a6c76379b60aba5dc.tar.gz | |
Refactor rtree to be lock-free.
Recent huge allocation refactoring associates huge allocations with
arenas, but it remains necessary to quickly look up huge allocation
metadata during reallocation/deallocation. A global radix tree remains
a good solution to this problem, but locking would have become the
primary bottleneck after (upcoming) migration of chunk management from
global to per arena data structures.
This lock-free implementation uses double-checked reads to traverse the
tree, so that in the steady state, each read or write requires only a
single atomic operation.
This implementation also assures that no more than two tree levels
actually exist, through a combination of careful virtual memory
allocation which makes large sparse nodes cheap, and skipping the root
node on x64 (possible because the top 16 bits are all 0 in practice).
Diffstat (limited to 'include/jemalloc/internal/chunk.h')
| -rw-r--r-- | include/jemalloc/internal/chunk.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/jemalloc/internal/chunk.h b/include/jemalloc/internal/chunk.h index 764b7ac..62ac3e7 100644 --- a/include/jemalloc/internal/chunk.h +++ b/include/jemalloc/internal/chunk.h @@ -35,7 +35,7 @@ extern malloc_mutex_t chunks_mtx; /* Chunk statistics. */ extern chunk_stats_t stats_chunks; -extern rtree_t *chunks_rtree; +extern rtree_t chunks_rtree; extern size_t chunksize; extern size_t chunksize_mask; /* (chunksize - 1). */ |