Created attachment 608236 [details] [diff] [review]
AIUI, JSScript::inlineData was added in bug 674251 to avoid a Mac-only regression on a benchmark. Mac builds now use jemalloc, so that sensitivity shouldn't be a problem any more.
Furthermore, removing inlineData reduces the size of JSScript on 64-bit from 208 bytes to 200 bytes. With 4064 bytes available for data per arena, this means we can fit 20 JSScripts per arena instead of 19. (If we halve JSScript size, as has been suggested for CPG, we'll fit 10 instead of 9).
As for the memory savings made by storing the data inline -- only 2 or 3% of all JSScripts are small enough to fit inline. So the increase in memory consumption from storing tiny scripts out-of-line is negligible compared to the savings from fitting more JSScripts per arena.
Comment on attachment 608236 [details] [diff] [review]