Rebuild spec: measurements after the second performance round

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

REBUILD.md

@@ -14,17 +14,27 @@ prefetch spool, leases, rule sets, fragment merger, settling), the node API
 (`edge:node`, `--processes`), the catalog and chunk store, NZBs and a name
 search. Measured on the workstation (4 cores, 100 Mbit, Eweka):
 
-- Edge worker, one core: ~190–215 k headers/s on recent a.b.boneless,
-  ~330 k on a 2013 a.b.ath range; ~0.66 GB peak per process. (Start:
-  73–103 k/s, 1.0–1.2 GB.)
-- NNTP: ~22–30 k overview lines/s per connection in chunks of 100 k
-  (Eweka takes ~1.5–2 s per command); connections don't slow each other.
-- End to end (coordinator with 10 connections, web server, Postgres and 3
-  worker processes on one 4-core machine): 244 k headers/s; the server side
-  used 10% (web) + 22% (coordinator) + 32% (Postgres) of a core.
+- Edge worker, one core: ~210–215 k headers/s on recent a.b.boneless,
+  ~330–340 k on a 2013 a.b.ath range; ~0.7–0.8 GB peak per process.
+  (Start: 73–103 k/s, 1.0–1.2 GB.) What's left is spread out (the
+  per-file key ~12%, GC ~10%, zlib ~10%, the scan ~6%).
+- NNTP: Eweka takes ~1.5–2 s per XOVER command; ~22–30 k lines/s per
+  connection in chunks of 100 k when the line allows; connections don't
+  slow each other.
+- Bandwidth: compressed XOVER is ~69 B per article on recent boneless
+  (100 k-article chunks of ~7 MB). The workstation's 100 Mbit line carries
+  ~140–150 k articles/s, which is where its end-to-end runs now stop (10
+  connections 90–99% busy, ~89 Mbit/s).
+- End to end at that rate (one 4-core machine): workers about half busy
+  each; server side ~17% (coordinator) + ~8% (web) + ~3% (Postgres) of a
+  core. (Before this round's fixes Postgres was at 32%: the merger's
+  neighbour query read every range per file.)
 - Storage: chunks 17.9–20.3 B per segment (format v2); a release ~1.1 KB.
-- For the whole target (528 B overview lines): ~4–6 days at 50 connections,
-  ~3 worker cores.
+- For the whole target (528 B overview lines): ~36 TB of compressed XOVER
+  to download. At 50 connections (~1–1.25 M lines/s, ~0.6–0.7 Gbit/s)
+  ~5–6 days, ~5–6 worker cores, two coordinator shards (one process
+  handles ~60 MB/s), under a core for web and Postgres. The line is the
+  limit below ~0.7 Gbit/s: at 1 Gbit, ~3.5 days at best.
 
 Not built yet: re-running ranges for a retracted rule (the counts and rule
 versions are recorded), deployment (Dockerfile, compose), phase 2.