The default V8 flags only set --max-old-space-size (a ceiling, not actual
use). The young generation (default 16MB per semi-space) plus V8's
memory-heavy codegen inflate RSS during parse and JS allocation. Add
--max-semi-space-size=4 and --optimize-for-size to the defaults.
Cuts RSS ~10-17% on real pages (ycombinator.com 170MB -> 141MB,
react.dev 94MB -> 83MB, wikipedia 58MB -> 53MB) with no measurable speed
cost: a JIT-sensitive 8M-iteration loop is unchanged (V8 still optimizes
hot paths), and the obstacle course stays 33/33 at the same latency.
Users can still override via --v8-flags.
SGavrl
b25cc8fc61