3 ms·
1 bit per byte would require an awful lot of memory access to find a free block. You would need something like a hierarchy of bitmaps to cut down on scanning.
by gliptic 8y ago
1 bit per byte would require an awful lot of memory access to find a free block. You would need something like a hierarchy of bitmaps to cut down on scanning.
- mabynogy 8y agoNo because you'll end up with the same problem elsewhere (handling blocks). If I'm correct tcmalloc memory overhead is around 4%. More overhead can be acceptable if the memory is less fragmented (less fragmentation, less cache misses, better compactness and better perfs).
- gliptic 8y agoWell, you're welcome to try, but it's not like free space bitmaps are unknown to allocator writers.