ISMM 2011 selected paper notes

• Cache Index-Aware Memory Allocation. Allocator of fixed-size headerless objects with sizes that are multiples of cache line size (e.g. object size 128 on cache lines of 64 bytes) may cause certain cache indices to be evicted often when objects uniformly map to the same cache line. Adding spacers (punctuated array) to these objects could break the affinity. NOTE(liulk):
• Cache index conflict should generally happen only at block level if the allocator uses superblocks to manage arenas.
• Knuth boundary tags are natural spacers used for variable sized object allocation, and would not suffer this problem.
• Compartmental Memory Management in a Modern Web Browser. Memory resources allocated for each origin (as in "same origin policy") is stored together in the same heap, and a web browser will have separate heaps for each origin. Although Chrome spawns a process for each tag, but this may not be practical for mobile devices where hardware address space isolation could be expensive. This also shortens garbage collection time because same-origin private heaps do not have reference to objects belonging to another origin.
• Multicore Garbage Collection with Local Heaps. Illustrates how mutation handling makes it hard to separate local and global heaps, and how despite the complicated mechanism, achieves little gain in scalability.
• Iterative Data-parallel Mark&Sweep on a GPU. Highlights challenges specific to GPU, namely the lack of deep recursion due to the relatively small size of video memory (~128MB) with no virtual memory and the large number of threads (1000+).