fix(runners): size limits from host memory share

scripts/gitea-actions/deploy-runner-config.xsh

@@ -20,6 +20,7 @@ HOSTS = {
 
 DEFAULT_MEM_FRACTION = 0.75
 DEFAULT_JOB_MEM_FRACTION = 0.9
+DEFAULT_HOST_MEM_SHARE = 0.25
 MIN_RUNNER_MEM_MIB = 1024
 MIN_JOB_MEM_MIB = 128
 
@@ -51,6 +52,20 @@ def parse_job_mem_fraction(argv):
         raise SystemExit("--job-mem-fraction must be > 0 and <= 1")
     return fraction
 
+
+def parse_host_mem_share(argv):
+    share = DEFAULT_HOST_MEM_SHARE
+    for arg in argv[1:]:
+        if arg.startswith("--host-mem-share="):
+            _, value = arg.split("=", 1)
+            try:
+                share = float(value)
+            except ValueError as exc:
+                raise SystemExit(f"Invalid --host-mem-share value: {value}") from exc
+    if share <= 0 or share > 1:
+        raise SystemExit("--host-mem-share must be > 0 and <= 1")
+    return share
+
 def ssh(host, cmd):
     proc = subprocess.run(
         [
@@ -328,44 +343,24 @@ def host_total_mem_mib(host):
     return int(int(mem_kib.strip()) / 1024.0)
 
 
-def host_mem_limit(host, fraction):
+def host_mem_limit(host, host_mem_share, fraction):
     total_mib = host_total_mem_mib(host)
-    target_mib = int(total_mib * fraction)
+    host_share_mib = int(total_mib * host_mem_share)
+    target_mib = int(host_share_mib * fraction)
     if target_mib < MIN_RUNNER_MEM_MIB:
         target_mib = MIN_RUNNER_MEM_MIB
-    return f"{target_mib}m", target_mib, f"host-total({total_mib}MiB)"
-
-
-def current_runner_baseline_mib(host, compose_text):
-    deploy_memory_value = find_service_memory_value(
-        compose_text,
-        {"act_runner_1", "act_runner_2", "runner1", "runner2"},
+    return (
+        f"{target_mib}m",
+        target_mib,
+        f"host-total({total_mib}MiB) * host-share({host_mem_share:.2f}) -> {host_share_mib}MiB * mem-fraction({fraction:.2f})",
     )
-    deploy_mib = parse_mem_value_to_mib(deploy_memory_value) if deploy_memory_value else None
-    if deploy_mib and deploy_mib > 0:
-        return deploy_mib, f"compose(deploy.memory={deploy_memory_value})"
-
-    compose_value = find_service_key_value(
-        compose_text,
-        {"act_runner_1", "act_runner_2", "runner1", "runner2"},
-        "mem_limit",
-    )
-    compose_mib = parse_mem_value_to_mib(compose_value) if compose_value else None
-    if compose_mib and compose_mib > 0:
-        return compose_mib, f"compose(mem_limit={compose_value})"
-
-    rc, inspect_mem = ssh(host, "docker inspect gitea-act-runner-1 --format '{{.HostConfig.Memory}}'")
-    if rc == 0:
-        inspect_mib = parse_mem_value_to_mib(inspect_mem)
-        if inspect_mib and inspect_mib > 0:
-            return inspect_mib, f"inspect(HostConfig.Memory={inspect_mem.strip()})"
-
-    return None, "none"
 
 
 mem_fraction = parse_mem_fraction(sys.argv)
 job_mem_fraction = parse_job_mem_fraction(sys.argv)
+host_mem_share = parse_host_mem_share(sys.argv)
 
+print(f"Host mem share: {host_mem_share:.2f}")
 print(f"Runner mem fraction: {mem_fraction:.2f}")
 print(f"Job mem fraction: {job_mem_fraction:.2f}")
 print("Fetching canonical runner config template")
@@ -389,18 +384,15 @@ with tempfile.TemporaryDirectory() as tmpdir:
             print("Could not read compose.yml")
             continue
 
-        baseline_mib, baseline_source = current_runner_baseline_mib(host, compose)
-        if baseline_mib is None:
-            try:
-                runner_mem_limit, runner_mem_mib, baseline_source = host_mem_limit(host, mem_fraction)
-            except RuntimeError as exc:
-                print(str(exc))
-                continue
-        else:
-            runner_mem_mib = int(baseline_mib * mem_fraction)
-            if runner_mem_mib < 1:
-                runner_mem_mib = 1
-            runner_mem_limit = f"{runner_mem_mib}m"
+        try:
+            runner_mem_limit, runner_mem_mib, baseline_source = host_mem_limit(
+                host,
+                host_mem_share,
+                mem_fraction,
+            )
+        except RuntimeError as exc:
+            print(str(exc))
+            continue
 
         print(f"runner_mem_baseline={baseline_source}")
         print(f"runner_mem_limit={runner_mem_limit} ({runner_mem_mib} MiB)")