Measure one sending loop against a thread a link, with and without push (028)

Five rounds of 1,000 bursts by one link, four links and one wire, four
builds in turns: a thread a link (966b82f), those threads with push
(threads-push.patch), the loop (99b2219), the loop with push (94e7bb8).
Medians: one link 597k, 923k, 525k, 897k sends/s; four links 506k,
799k, 268k, 800k; the wire as it was, 789k to 794k.

1 files changed, 36 insertions, 0 deletions

diff --git a/research/experiments/028-one-sending-loop/runs.sh b/research/experiments/028-one-sending-loop/runs.sh
new file mode 100755
index 0000000..65eb51d
--- /dev/null
+++ b/research/experiments/028-one-sending-loop/runs.sh
@@ -0,0 +1,36 @@
+#!/bin/sh
+# The runs of docs/design/017's 2b, from the repository's root, in steps
+# (a step at a time: a background job may be stopped after half an hour).
+#   runs.sh build   the builds, each in /tmp/pure-028/NAME with its
+#                   pure-crypto.so: before (a thread a link, 3791ab8),
+#                   threads-push (before with threads-push.patch: the
+#                   owner pushes a turn's sends at once), loop (one
+#                   sending loop, 32f96b3), push (the loop with push,
+#                   6d3c3c2)
+#   runs.sh links   five rounds of 1,000 bursts by one link, four links and
+#                   one wire, the builds in turns, once the last minute's
+#                   load is below 1.5
+set -e
+out=research/experiments/028-one-sending-loop
+builds=/tmp/pure-028
+case "$1" in
+build)
+    for pair in before:3791ab8 threads-push:3791ab8 loop:32f96b3 push:6d3c3c2; do
+        name=${pair%%:*} commit=${pair#*:}
+        rm -rf $builds/src-$name
+        git worktree add -f -q --detach $builds/src-$name $commit
+        if [ $name = threads-push ]; then git -C $builds/src-$name apply "$PWD/$out/threads-push.patch"; fi
+        make -s -C $builds/src-$name build/pure-serve build/pure-crypto.so
+        mkdir -p $builds/$name
+        cp $builds/src-$name/build/pure-serve $builds/src-$name/build/pure-crypto.so $builds/$name/
+        git worktree remove --force $builds/src-$name
+    done ;;
+links)
+    until awk '{ exit !($1 < 1.5) }' /proc/loadavg; do sleep 10; done
+    echo "$(uptime)" > $out/2026-10-01-links-load.txt
+    python3 $out/sends.py 5 1000 link,links4,wire before=$builds/before/pure-serve \
+        threads-push=$builds/threads-push/pure-serve loop=$builds/loop/pure-serve push=$builds/push/pure-serve \
+        > $out/2026-10-01-links-linux-aarch64.jsonl
+    echo "$(uptime)" >> $out/2026-10-01-links-load.txt ;;
+*) echo "runs.sh build|links" >&2; exit 2 ;;
+esac