JavaScript:SpiderMonkey:Arena Allocation: Difference between revisions

=== Plans ===

'''Time-deferred "soft" release''' — it was observed in the execution of imacro_asm.js that the regexp pool thrashes quite a bit: a recurring free/alloc of a single arena occurs with each simple regular expression match. By sticking a timestamp on the arena pool and having the garbage collector release the outstanding arenas at a later time we can avoid this overhead in the common case.

'''Determine optimal arena chunk policy''' — the arena chunk sizes should mesh with the virtual memory subsystem as nicely as possible. For example, mallocing PAGE_SIZE + 1 byte is probably not ideal. It appears that OS X and Linux follow the same allocation patterns with their malloc implementations WRT their page sizes from [http://bitbucket.org/cdleary/vmem-chunk-allocation/src these experiments]. Further investigation would probably be helpful in determining an overall policy. References: [https://bugzilla.mozilla.org/show_bug.cgi?id=421435 421435], [https://bugzilla.mozilla.org/show_bug.cgi?id=561286 561286]