asm-gc gains (tcp-sendfile socket path) → builtin (90 lines) that issues
SYS_SENDFILE(40) in a loop, streaming a file from fd → socket with no bounce
through the Lumbda heap. Zero-copy kernel path for large responses.
examples/http-static-server-sendfile.lsp (hybrid): small assets
(≤ 16 KB) stay inline-cached as full HTTP responses; large assets cache
only headers and stream the body via tcp-sendfile. 4-way race on
i5-8350U, 100 PDF requests (2.56 MiB), concurrency 8:
uncached 159 req/s 406 MiB/s 15.5 MB RSS
cached 238 req/s 603 MiB/s 7.2 MB RSS
sendfile 480 req/s 1226 MiB/s 4.2 MB RSS
caddy 485 req/s 1238 MiB/s 37.1 MB RSS
sendfile lands within 2% of caddy on throughput with 9x less peak RSS in
a 27 KB binary vs caddy's 38 MB (1400x smaller).
examples/http-static-server-adaptive.lsp (learning preload): per-URL hit
counter persisted to www.hits every N requests. At boot, ranks and
preloads top *cache-max* URLs from the prior run's data (cold-start
falls back to a seed list). Cold requests beyond the seed promote on
first hit. Drops heap-restore arena pattern since the server mutates
persistent state every request; relies on GC build's mark-sweep.
tests/bench-www-race.sh: adds sendfile variant on port 8083, auto-sizes
PDF byte count from the on-disk whitepaper so a whitepaper rebuild
doesn't desync the MiB/s calc.
Whitepaper §11.7 "Static File Serving: Cache, Sendfile, and Adaptive
Preload" documents the four variants, benchmark table, and the
arena-vs-mutation tradeoff. §13 Future Work adds DAG-of-hot-paths
predictive preload as the direction for > 1000-resource deployments
where frequency-only ranking is too narrow.
russell@unturf.com
94b29421ed